text:
Heat exchanger
From Wikipedia, the free encyclopedia
Jump to: navigation, search
Tubular heat exchanger
A heat exchanger is a device used to transfer heat between a solid object and a fluid, or between two or more fluids. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact.[1] They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant.
Contents
[hide]
1 Flow arrangement
2 Types
2.1 Shell and tube heat exchanger
2.2 Plate heat exchangers
2.3 Plate and shell heat exchanger
2.4 Adiabatic wheel heat exchanger
2.5 Plate fin heat exchanger
2.6 Pillow plate heat exchanger
2.7 Fluid heat exchangers
2.8 Waste heat recovery units
2.9 Dynamic scraped surface heat exchanger
2.10 Phase-change heat exchangers
2.11 Direct contact heat exchangers
2.12 Microchannel heat exchangers
3 HVAC air coils
4 Helical-coil heat exchangers
5 Spiral heat exchangers
5.1 Construction
5.2 Self cleaning
5.3 Flow arrangements
5.4 Applications
6 Selection
7 Monitoring and maintenance
7.1 Fouling
7.2 Maintenance
8 In nature
8.1 Humans
8.2 Birds, fish, marine mammals
8.3 Carotid rete
9 In industry
10 In aircraft
11 Current market and forecast
12 A model of a simple heat exchanger
13 See also
14 References
15 External links
Flow arrangement[edit]
Countercurrent (A) and parallel (B) flows
Fig. 1: Shell and tube heat exchanger, single pass (1–1 parallel flow)
Fig. 2: Shell and tube heat exchanger, 2-pass tube side (1–2 crossflow)
Fig. 3: Shell and tube heat exchanger, 2-pass shell side, 2-pass tube side (2-2 countercurrent)
There are three primary classifications of heat exchangers according to their flow arrangement. In parallel-flow heat exchangers, the two fluids enter the exchanger at the same end, and travel in parallel to one another to the other side. In counter-flow heat exchangers the fluids enter the exchanger from opposite ends. The counter current design is the most efficient, in that it can transfer the most heat from the heat (transfer) medium per unit mass due to the fact that the average temperature difference along any unit length is higher. See countercurrent exchange. In a cross-flow heat exchanger, the fluids travel roughly perpendicular to one another through the exchanger.
For efficiency, heat exchangers are designed to maximize the surface area of the wall between the two fluids, while minimizing resistance to fluid flow through the exchanger. The exchanger's performance can also be affected by the addition of fins or corrugations in one or both directions, which increase surface area and may channel fluid flow or induce turbulence.
The driving temperature across the heat transfer surface varies with position, but an appropriate mean temperature can be defined. In most simple systems this is the "log mean temperature difference" (LMTD). Sometimes direct knowledge of the LMTD is not available and the NTU method is used.
Types[edit]
Double pipe heat exchangers are the simplest exchangers used in industries. On one hand, these heat exchangers are cheap for both design and maintenance, making them a good choice for small industries. On the other hand, their low efficiency coupled with the high space occupied in large scales, has led modern industries to use more efficient heat exchangers like shell and tube or plate. However, since double pipe heat exchangers are simple, they are used to teach heat exchanger design basics to students as the fundamental rules for all heat exchangers are the same.
Shell and tube heat exchanger[edit]
A shell and tube heat exchanger
Main article: Shell and tube heat exchanger
Shell and tube heat exchangers consist of series of tubes. One set of these tubes contains the fluid that must be either heated or cooled. The second fluid runs over the tubes that are being heated or cooled so that it can either provide the heat or absorb the heat required. A set of tubes is called the tube bundle and can be made up of several types of tubes: plain, longitudinally finned, etc. Shell and tube heat exchangers are typically used for high-pressure applications (with pressures greater than 30 bar and temperatures greater than 260 °C).[2] This is because the shell and tube heat exchangers are robust due to their shape.
Several thermal design features must be considered when designing the tubes in the shell and tube heat exchangers: There can be many variations on the shell and tube design. Typically, the ends of each tube are connected to plenums (sometimes called water boxes) through holes in tubesheets. The tubes may be straight or bent in the shape of a U, called U-tubes.
Tube diameter: Using a small tube diameter makes the heat exchanger both economical and compact. However, it is more likely for the heat exchanger to foul up faster and the small size makes mechanical cleaning of the fouling difficult. To prevail over the fouling and cleaning problems, larger tube diameters can be used. Thus to determine the tube diameter, the available space, cost and fouling nature of the fluids must be considered.
Tube thickness: The thickness of the wall of the tubes is usually determined to ensure:
There is enough room for corrosion
That flow-induced vibration has resistance
Axial strength
Availability of spare parts
Hoop strength (to withstand internal tube pressure)
Buckling strength (to withstand overpressure in the shell)
Tube length: heat exchangers are usually cheaper when they have a smaller shell diameter and a long tube length. Thus, typically there is an aim to make the heat exchanger as long as physically possible whilst not exceeding production capabilities. However, there are many limitations for this, including space available at the installation site and the need to ensure tubes are available in lengths that are twice the required length (so they can be withdrawn and replaced). Also, long, thin tubes are difficult to take out and replace.
Tube pitch: when designing the tubes, it is practical to ensure that the tube pitch (i.e., the centre-centre distance of adjoining tubes) is not less than 1.25 times the tubes' outside diameter. A larger tube pitch leads to a larger overall shell diameter, which leads to a more expensive heat exchanger.
Tube corrugation: this type of tubes, mainly used for the inner tubes, increases the turbulence of the fluids and the effect is very important in the heat transfer giving a better performance.
Tube Layout: refers to how tubes are positioned within the shell. There are four main types of tube layout, which are, triangular (30°), rotated triangular (60°), square (90°) and rotated square (45°). The triangular patterns are employed to give greater heat transfer as they force the fluid to flow in a more turbulent fashion around the piping. Square patterns are employed where high fouling is experienced and cleaning is more regular.
Baffle Design: baffles are used in shell and tube heat exchangers to direct fluid across the tube bundle. They run perpendicularly to the shell and hold the bundle, preventing the tubes from sagging over a long length. They can also prevent the tubes from vibrating. The most common type of baffle is the segmental baffle. The semicircular segmental baffles are oriented at 180 degrees to the adjacent baffles forcing the fluid to flow upward and downwards between the tube bundle. Baffle spacing is of large thermodynamic concern when designing shell and tube heat exchangers. Baffles must be spaced with consideration for the conversion of pressure drop and heat transfer. For thermo economic optimization it is suggested that the baffles be spaced no closer than 20% of the shell’s inner diameter. Having baffles spaced too closely causes a greater pressure drop because of flow redirection. Consequently, having the baffles spaced too far apart means that there may be cooler spots in the corners between baffles. It is also important to ensure the baffles are spaced close enough that the tubes do not sag. The other main type of baffle is the disc and doughnut baffle, which consists of two concentric baffles. An outer, wider baffle looks like a doughnut, whilst the inner baffle is shaped like a disk. This type of baffle forces the fluid to pass around each side of the disk then through the doughnut baffle generating a different type of fluid flow.
Fixed tube liquid-cooled heat exchangers especially suitable for marine and harsh applications can be assembled with brass shells, copper tubes, brass baffles, and forged brass integral end hubs.[3] (See: Copper in heat exchangers).
Conceptual diagram of a plate and frame heat exchanger.
A single plate heat exchanger
An interchangeable plate heat exchanger applied to the system of a swimming pool
Plate heat exchangers[edit]
Main article: Plate heat exchanger
Another type of heat exchanger is the plate heat exchanger. These exchangers are composed of many thin, slightly separated plates that have very large surface areas and small fluid flow passages for heat transfer. Advances in gasket and brazing technology have made the plate-type heat exchanger increasingly practical. In HVAC applications, large heat exchangers of this type are called plate-and-frame; when used in open loops, these heat exchangers are normally of the gasket type to allow periodic disassembly, cleaning, and inspection. There are many types of permanently bonded plate heat exchangers, such as dip-brazed, vacuum-brazed, and welded plate varieties, and they are often specified for closed-loop applications such as refrigeration. Plate heat exchangers also differ in the types of plates that are used, and in the configurations of those plates. Some plates may be stamped with "chevron", dimpled, or other patterns, where others may have machined fins and/or grooves.
When compared to shell and tube exchangers, the stacked-plate arrangement typically has lower volume and cost. Another difference between the two is that plate exchangers typically serve low to medium pressure fluids, compared to medium and high pressures of shell and tube. A third and important difference is that plate exchangers employ more countercurrent flow rather than cross current flow, which allows lower approach temperature differences, high temperature changes, and increased efficiencies.
Plate and shell heat exchanger[edit]
A third type of heat exchanger is a plate and shell heat exchanger, which combines plate heat exchanger with shell and tube heat exchanger technologies. The heart of the heat exchanger contains a fully welded circular plate pack made by pressing and cutting round plates and welding them together. Nozzles carry flow in and out of the platepack (the 'Plate side' flowpath). The fully welded platepack is assembled into an outer shell that creates a second flowpath ( the 'Shell side'). Plate and shell technology offers high heat transfer, high pressure, high operating temperature, uling and close approach temperature. In particular, it does completely without gaskets, which provides security against leakage at high pressures and temperatures.
Adiabatic wheel heat exchanger[edit]
A fourth type of heat exchanger uses an intermediate fluid or solid store to hold heat, which is then moved to the other side of the heat exchanger to be released. Two examples of this are adiabatic wheels, which consist of a large wheel with fine threads rotating through the hot and cold fluids, and fluid heat exchangers.
Plate fin heat exchanger[edit]
Main article: Plate fin heat exchanger
This type of heat exchanger uses "sandwiched" passages containing fins to increase the effectiveness of the unit. The designs include crossflow and counterflow coupled with various fin configurations such as straight fins, offset fins and wavy fins.
Plate and fin heat exchangers are usually made of aluminum alloys, which provide high heat transfer efficiency. The material enables the system to operate at a lower temperature difference and reduce the weight of the equipment. Plate and fin heat exchangers are mostly used for low temperature services such as natural gas, helium and oxygen liquefaction plants, air separation plants and transport industries such as motor and aircraft engines.
Advantages of plate and fin heat exchangers:
High heat transfer efficiency especially in gas treatment
Larger heat transfer area
Approximately 5 times lighter in weight than that of shell and tube heat exchanger.
Able to withstand high pressure
Disadvantages of plate and fin heat exchangers:
Might cause clogging as the pathways are very narrow
Difficult to clean the pathways
Aluminium alloys are susceptible to Mercury Liquid Embrittlement Failure
Pillow plate heat exchanger[edit]
A pillow plate exchanger is commonly used in the dairy industry for cooling milk in large direct-expansion stainless steel bulk tanks. The pillow plate allows for cooling across nearly the entire surface area of the tank, without gaps that would occur between pipes welded to the exterior of the tank.
The pillow plate is constructed using a thin sheet of metal spot-welded to the surface of another thicker sheet of metal. The thin plate is welded in a regular pattern of dots or with a serpentine pattern of weld lines. After welding the enclosed space is pressurised with sufficient force to cause the thin metal to bulge out around the welds, providing a space for heat exchanger liquids to flow, and creating a characteristic appearance of a swelled pillow formed out of metal.
Fluid heat exchangers[edit]
This is a heat exchanger with a gas passing upwards through a shower of fluid (often water), and the fluid is then taken elsewhere before being cooled. This is commonly used for cooling gases whilst also removing certain impurities, thus solving two problems at once. It is widely used in espresso machines as an energy-saving method of cooling super-heated water to use in the extraction of espresso.
Waste heat recovery units[edit]
This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (March 2017) (Learn how and when to remove this template message)
A waste heat recovery unit (WHRU) is a heat exchanger that recovers heat from a hot gas stream while transferring it to a working medium, typically water or oils. The hot gas stream can be the exhaust gas from a gas turbine or a diesel engine or a waste gas from industry or refinery.
Large systems with high volume and temperature gas streams, typical in industry, can benefit from steam Rankine cycle (SRC) in a waste heat recovery unit, but these cycles are too expensive for small systems. The recovery of heat from low temperature systems requires different working fluids than steam.
An organic Rankine cycle (ORC) waste heat recovery unit can be more efficient at low temperature range using refrigerants that boil at lower temperatures than water. Typical organic refrigerants are ammonia, pentafluoropropane (R-245fa and R-245ca), and toluene.
The refrigerant is boiled by the heat source in the evaporator to produce super-heated vapor. This fluid is expanded in the turbine to convert thermal energy to kinetic energy, that is converted to electricity in the electrical generator. This energy transfer process decreases the temperature of the refrigerant that, in turn, condenses. The cycle is closed and completed using a pump to send the fluid back to the evaporator.
Dynamic scraped surface heat exchanger[edit]
Another type of heat exchanger is called "(dynamic) scraped surface heat exchanger". This is mainly used for heating or cooling with high-viscosity products, crystallization processes, evaporation and high-fouling applications. Long running times are achieved due to the continuous scraping of the surface, thus avoiding fouling and achieving a sustainable heat transfer rate during the process.
Phase-change heat exchangers[edit]
Typical kettle reboiler used for industrial distillation towers
Typical water-cooled surface condenser
In addition to heating up or cooling down fluids in just a single phase, heat exchangers can be used either to heat a liquid to evaporate (or boil) it or used as condensers to cool a vapor and condense it to a liquid. In chemical plants and refineries, reboilers used to heat incoming feed for distillation towers are often heat exchangers.[4][5]
Distillation set-ups typically use condensers to condense distillate vapors back into liquid.
Power plants that use steam-driven turbines commonly use heat exchangers to boil water into steam. Heat exchangers or similar units for producing steam from water are often called boilers or steam generators.
In the nuclear power plants called pressurized water reactors, special large heat exchangers pass heat from the primary (reactor plant) system to the secondary (steam plant) system, producing steam from water in the process. These are called steam generators. All fossil-fueled and nuclear power plants using steam-driven turbines have surface condensers to convert the exhaust steam from the turbines into condensate (water) for re-use.[6][7]
To conserve energy and cooling capacity in chemical and other plants, regenerative heat exchangers can transfer heat from a stream that must be cooled to another stream that must be heated, such as distillate cooling and reboiler feed pre-heating.
This term can also refer to heat exchangers that contain a material within their structure that has a change of phase. This is usually a solid to liquid phase due to the small volume difference between these states. This change of phase effectively acts as a buffer because it occurs at a constant temperature but still allows for the heat exchanger to accept additional heat. One example where this has been investigated is for use in high power aircraft electronics.
Heat exchangers functioning in multiphase flow regimes may be subject to the Ledinegg instability.
Direct contact heat exchangers[edit]
Direct contact heat exchangers involve heat transfer between hot and cold streams of two phases in the absence of a separating wall.[8] Thus such heat exchangers can be classified as:
Gas – liquid
Immiscible liquid – liquid
Solid-liquid or solid – gas
Most direct contact heat exchangers fall under the Gas – Liquid category, where heat is transferred between a gas and liquid in the form of drops, films or sprays.[2]
Such types of heat exchangers are used predominantly in air conditioning, humidification, industrial hot water heating, water cooling and condensing plants.[9]
Phases[10]
Continuous phase
Driving force
Change of phase
Examples
Gas – Liquid Gas Gravity No Spray columns, packed columns
Yes Cooling towers, falling droplet evaporators
Forced No Spray coolers/quenchers
Liquid flow Yes Spray condensers/evaporation, jet condensers
Liquid Gravity No Bubble columns, perforated tray columns
Yes Bubble column condensers
Forced No Gas spargers
Gas flow Yes Direct contact evaporators, submerged combustion
Microchannel heat exchangers[edit]
Main article: Micro heat exchanger
Micro heat exchangers, Micro-scale heat exchangers, or microstructured heat exchangers are heat exchangers in which (at least one) fluid flows in lateral confinements with typical dimensions below 1 mm. The most typical such confinement are microchannels, which are channels with a hydraulic diameter below 1 mm. Microchannel heat exchangers can be made from metal, ceramic,[11] Microchannel heat exchangers can be used for many applications including:
high-performance aircraft gas turbine engines[12]
heat pumps[13]
air conditioning [14]
HVAC air coils[edit]
One of the widest uses of heat exchangers is for air conditioning of buildings and vehicles. This class of heat exchangers is commonly called air coils, or just coils due to their often-serpentine internal tubing. Liquid-to-air, or air-to-liquid HVAC coils are typically of modified crossflow arrangement. In vehicles, heat coils are often called heater cores.
On the liquid side of these heat exchangers, the common fluids are water, a water-glycol solution, steam, or a refrigerant. For heating coils, hot water and steam are the most common, and this heated fluid is supplied by boilers, for example. For cooling coils, chilled water and refrigerant are most common. Chilled water is supplied from a chiller that is potentially located very far away, but refrigerant must come from a nearby condensing unit. When a refrigerant is used, the cooling coil is the evaporator in the vapor-compression refrigeration cycle. HVAC coils that use this direct-expansion of refrigerants are commonly called DX coils. Some DX coils are "microchannel" type.[15]
On the air side of HVAC coils a significant difference exists between those used for heating, and those for cooling. Due to psychrometrics, air that is cooled often has moisture condensing out of it, except with extremely dry air flows. Heating some air increases that airflow's capacity to hold water. So heating coils need not consider moisture condensation on their air-side, but cooling coils must be adequately designed and selected to handle their particular latent (moisture) as well as the sensible (cooling) loads. The water that is removed is called condensate.
For many climates, water or steam HVAC coils can be exposed to freezing conditions. Because water expands upon freezing, these somewhat expensive and difficult to replace thin-walled heat exchangers can easily be damaged or destroyed by just one freeze. As such, freeze protection of coils is a major concern of HVAC designers, installers, and operators.
The introduction of indentations placed within the heat exchange fins controlled condensation, allowing water molecules to remain in the cooled air. This invention allowed for refrigeration without icing of the cooling mechanism.[16]
The heat exchangers in direct-combustion furnaces, typical in many residences, are not 'coils'. They are, instead, gas-to-air heat exchangers that are typically made of stamped steel sheet metal. The combustion products pass on one side of these heat exchangers, and air to heat on the other. A cracked heat exchanger is therefore a dangerous situation that requires immediate attention because combustion products may enter living space.
Helical-coil heat exchangers[edit]
Helical-Coil Heat Exchanger sketch, which consists of a shell, core, and tubes (Scott S. Haraburda design).
Although double-pipe heat exchangers are the simplest to design, the better choice in the following cases would be the helical-coil heat exchanger (HCHE):
The main advantage of the HCHE, like that for the SHE, is its highly efficient use of space, especially when it’s limited and not enough straight pipe can be laid.[17]
Under conditions of low flowrates (or laminar flow), such that the typical shell-and-tube exchangers have low heat-transfer coefficients and becoming uneconomical.[17]
When there is low pressure in one of the fluids, usually from accumulated pressure drops in other process equipment.[17]
When one of the fluids has components in multiple phases (solids, liquids, and gases), which tends to create mechanical problems during operations, such as plugging of small-diameter tubes.[18] Cleaning of helical coils for these multiple-phase fluids can prove to be more difficult than its shell and tube counterpart; however the helical coil unit would require cleaning less often.
These have been used in the nuclear industry as a method for exchanging heat in a sodium system for large liquid metal fast breeder reactors since the early 1970s, using an HCHE device invented by Charles E. Boardman and John H. Germer.[19] There are several simple methods for designing HCHE for all types of manufacturing industries, such as using the Ramachandra K. Patil (et al.) method from India and the Scott S. Haraburda method from the United States.[17][18]
However, these are based upon assumptions of estimating inside heat transfer coefficient, predicting flow around the outside of the coil, and upon constant heat flux.[20] Yet, recent experimental data revealed that the empirical correlations are quite in agreement for designing circular and square pattern HCHEs.[21] During studies published in 2015, several researchers found that the boundary conditions of the outer wall of exchangers were essentially constant heat flux conditions in power plant boilers, condensers and evaporators; while convective heat transfer conditions were more appropriate in food, automobile and process industries.[22]
Spiral heat exchangers[edit]
Schematic drawing of a spiral heat exchanger.
A modification to the perpendicular flow of the typical HCHE involves the replacement of shell with another coiled tube, allowing the two fluids to flow parallel to one another, and which requires the use of different design calculations.[23] These are the Spiral Heat Exchangers (SHE), which may refer to a helical (coiled) tube configuration, more generally, the term refers to a pair of flat surfaces that are coiled to form the two channels in a counter-flow arrangement. Each of the two channels has one long curved path. A pair of fluid ports are connected tangentially to the outer arms of the spiral, and axial ports are common, but optional.[24]
The main advantage of the SHE is its highly efficient use of space. This attribute is often leveraged and partially reallocated to gain other improvements in performance, according to well known tradeoffs in heat exchanger design. (A notable tradeoff is capital cost vs operating cost.) A compact SHE may be used to have a smaller footprint and thus lower all-around capital costs, or an oversized SHE may be used to have less pressure drop, less pumping energy, higher thermal efficiency, and lower energy costs.
Construction[edit]
The distance between the sheets in the spiral channels is maintained by using spacer studs that were welded prior to rolling. Once the main spiral pack has been rolled, alternate top and bottom edges are welded and each end closed by a gasketed flat or conical cover bolted to the body. This ensures no mixing of the two fluids occurs. Any leakage is from the periphery cover to the atmosphere, or to a passage that contains the same fluid.[25]
Self cleaning[edit]
Spiral heat exchangers are often used in the heating of fluids that contain solids and thus tend to foul the inside of the heat exchanger. The low pressure drop lets the SHE handle fouling more easily. The SHE uses a “self cleaning” mechanism, whereby fouled surfaces cause a localized increase in fluid velocity, thus increasing the drag (or fluid friction) on the fouled surface, thus helping to dislodge the blockage and keep the heat exchanger clean. "The internal walls that make up the heat transfer surface are often rather thick, which makes the SHE very robust, and able to last a long time in demanding environments."[citation needed] They are also easily cleaned, opening out like an oven where any buildup of foulant can be removed by pressure washing.
Self-cleaning water filters are used to keep the system clean and running without the need to shut down or replace cartridges and bags.
Flow arrangements[edit]
A comparison between the operations and effects of a cocurrent and a countercurrent flow exchange system is depicted by the upper and lower diagrams respectively. In both it is assumed (and indicated) that red has a higher value (e.g. of temperature) than blue and that the property being transported in the channels therefore flows from red to blue. Note that channels are contiguous if effective exchange is to occur (i.e. there can be no gap between the channels).
There are three main types of flows in a spiral heat exchanger:
Counter-current Flow: Fluids flow in opposite directions. These are used for liquid-liquid, condensing and gas cooling applications. Units are usually mounted vertically when condensing vapour and mounted horizontally when handling high concentrations of solids.
Spiral Flow/Cross Flow: One fluid is in spiral flow and the other in a cross flow. Spiral flow passages are welded at each side for this type of spiral heat exchanger. This type of flow is suitable for handling low density gas, which passes through the cross flow, avoiding pressure loss. It can be used for liquid-liquid applications if one liquid has a considerably greater flow rate than the other.
Distributed Vapour/Spiral flow: This design is that of a condenser, and is usually mounted vertically. It is designed to cater for the sub-cooling of both condensate and non-condensables. The coolant moves in a spiral and leaves via the top. Hot gases that enter leave as condensate via the bottom outlet.
Applications[edit]
The Spiral heat exchanger is good for applications such as pasteurization, digester heating, heat recovery, pre-heating (see: recuperator), and effluent cooling. For sludge treatment, SHEs are generally smaller than other types of heat exchangers.[citation needed] These are used to transfer the heat.
Selection[edit]
Due to the many variables involved, selecting optimal heat exchangers is challenging. Hand calculations are possible, but many iterations are typically needed. As such, heat exchangers are most often selected via computer programs, either by system designers, who are typically engineers, or by equipment vendors.
To select an appropriate heat exchanger, the system designers (or equipment vendors) would firstly consider the design limitations for each heat exchanger type. Though cost is often the primary criterion, several other selection criteria are important:
High/low pressure limits
Thermal performance
Temperature ranges
Product mix (liquid/liquid, particulates or high-solids liquid)
Pressure drops across the exchanger
Fluid flow capacity
Cleanability, maintenance and repair
Materials required for construction
Ability and ease of future expansion
Material selection, such as copper, aluminium, carbon steel, stainless steel, nickel alloys, ceramic, polymer, and titanium.
Small-diameter coil technologies are becoming more popular in modern air conditioning and refrigeration systems because they have better rates of heat transfer than conventional sized condenser and evaporator coils with round copper tubes and aluminum or copper fin that have been the standard in the HVAC industry. Small diameter coils can withstand the higher pressures required by the new generation of environmentally friendlier refrigerants. Two small diameter coil technologies are currently available for air conditioning and refrigeration products: copper microgroove[26] and brazed aluminum microchannel.[27]
Choosing the right heat exchanger (HX) requires some knowledge of the different heat exchanger types, as well as the environment where the unit must operate. Typically in the manufacturing industry, several differing types of heat exchangers are used for just one process or system to derive the final product. For example, a kettle HX for pre-heating, a double pipe HX for the ‘carrier’ fluid and a plate and frame HX for final cooling. With sufficient knowledge of heat exchanger types and operating requirements, an appropriate selection can be made to optimise the process.[28]
Monitoring and maintenance[edit]
Online monitoring of commercial heat exchangers is done by tracking the overall heat transfer coefficient. The overall heat transfer coefficient tends to decline over time due to fouling.
U=Q/AΔTlm
By periodically calculating the overall heat transfer coefficient from exchanger flow rates and temperatures, the owner of the heat exchanger can estimate when cleaning the heat exchanger is economically attractive.
Integrity inspection of plate and tubular heat exchanger can be tested in situ by the conductivity or helium gas methods. These methods confirm the integrity of the plates or tubes to prevent any cross contamination and the condition of the gaskets.
Mechanical integrity monitoring of heat exchanger tubes may be conducted through Nondestructive methods such as eddy current testing.
Fouling[edit]
Main article: Fouling
A heat exchanger in a steam power station contaminated with macrofouling.
Fouling occurs when impurities deposit on the heat exchange surface. Deposition of these impurities can decrease heat transfer effectiveness significantly over time and are caused by:
Low wall shear stress
Low fluid velocities
High fluid velocities
Reaction product solid precipitation
Precipitation of dissolved impurities due to elevated wall temperatures
The rate of heat exchanger fouling is determined by the rate of particle deposition less re-entrainment/suppression. This model was originally proposed in 1959 by Kern and Seaton.
Crude Oil Exchanger Fouling. In commercial crude oil refining, crude oil is heated from 21 °C (70 °F) to 343 °C (649 °F) prior to entering the distillation column. A series of shell and tube heat exchangers typically exchange heat between crude oil and other oil streams to heat the crude to 260 °C (500 °F) prior to heating in a furnace. Fouling occurs on the crude side of these exchangers due to asphaltene insolubility. The nature of asphaltene solubility in crude oil was successfully modeled by Wiehe and Kennedy.[29] The precipitation of insoluble asphaltenes in crude preheat trains has been successfully modeled as a first order reaction by Ebert and Panchal[30] who expanded on the work of Kern and Seaton.
Cooling Water Fouling. Cooling water systems are susceptible to fouling. Cooling water typically has a high total dissolved solids content and suspended colloidal solids. Localized precipitation of dissolved solids occurs at the heat exchange surface due to wall temperatures higher than bulk fluid temperature. Low fluid velocities (less than 3 ft/s) allow suspended solids to settle on the heat exchange surface. Cooling water is typically on the tube side of a shell and tube exchanger because it's easy to clean. To prevent fouling, designers typically ensure that cooling water velocity is greater than 0.9 m/s and bulk fluid temperature is maintained less than 60 °C (140 °F). Other approaches to control fouling control combine the “blind” application of biocides and anti-scale chemicals with periodic lab testing.
Maintenance[edit]
Plate and frame heat exchangers can be disassembled and cleaned periodically.[31] Tubular heat exchangers can be cleaned by such methods as acid cleaning, sandblasting, high-pressure water jet, bullet cleaning, or drill rods.
In large-scale cooling water systems for heat exchangers, water treatment such as purification, addition of chemicals, and testing, is used to minimize fouling of the heat exchange equipment. Other water treatment is also used in steam systems for power plants, etc. to minimize fouling and corrosion of the heat exchange and other equipment.
A variety of companies have started using water borne oscillations technology to prevent biofouling. Without the use of chemicals, this type of technology has helped in providing a low-pressure drop in heat exchangers.
In nature[edit]
Humans[edit]
The human nasal passages serve as a heat exchanger, which warms air being inhaled and cools air being exhaled. Its effectiveness can be demonstrated by putting the hand in front of the face and exhaling, first through the nose and then through the mouth. Air exhaled through the nose is substantially cooler.[32][33] This effect can be enhanced with clothing, by, for example, wearing a scarf over the face while breathing in cold weather.
In species that have external testes (such as humans), the artery to the testis is surrounded by a mesh of veins called the pampiniform plexus. This cools the blood heading to the testis, while reheating the returning blood.
Birds, fish, marine mammals[edit]
Countercurrent exchange conservation circuit
Further information: Countercurrent exchange in biological systems
"Countercurrent" heat exchangers occur naturally in the circulation system of fish, whales and other marine mammals. Arteries to the skin carrying warm blood are intertwined with veins from the skin carrying cold blood, causing the warm arterial blood to exchange heat with the cold venous blood. This reduces the overall heat loss in cold waters. Heat exchangers are also present in the tongue of baleen whales as large volumes of water flow through their mouths.[34][35] Wading birds use a similar system to limit heat losses from their body through their legs into the water.
Carotid rete[edit]
The carotid rete is a counter-current heat exchanging organ in some ungulates. The blood ascending the carotid arteries on its way to the brain, flows via a network of vessels where heat is discharged to the veins of cooler blood descending from the nasal passages. The carotid rete allows Thomson's gazelle to maintain its brain almost 3 °C (5.4 °F) cooler than the rest of the body, and therefore aids in tolerating bursts in metabolic heat production such as associated with outrunning cheetahs (during which the body temperature exceeds the maximum temperature at which the brain could function).[36]
In industry[edit]
Heat exchangers are widely used in industry both for cooling and heating large scale industrial processes. The type and size of heat exchanger used can be tailored to suit a process depending on the type of fluid, its phase, temperature, density, viscosity, pressures, chemical composition and various other thermodynamic properties.
In many industrial processes there is waste of energy or a heat stream that is being exhausted, heat exchangers can be used to recover this heat and put it to use by heating a different stream in the process. This practice saves a lot of money in industry, as the heat supplied to other streams from the heat exchangers would otherwise come from an external source that is more expensive and more harmful to the environment.
Heat exchangers are used in many industries, including:
Waste water treatment
Refrigeration
Wine and beer making
Petroleum refining
nuclear power
In waste water treatment, heat exchangers play a vital role in maintaining optimal temperatures within anaerobic digesters to promote the growth of microbes that remove pollutants. Common types of heat exchangers used in this application are the double pipe heat exchanger as well as the plate and frame heat exchanger.
In aircraft[edit]
In commercial aircraft heat exchangers are used to take heat from the engine's oil system to heat cold fuel.[37] This improves fuel efficiency, as well as reduces the possibility of water entrapped in the fuel freezing in components.[38]
Current market and forecast[edit]
Estimated at US$42.7 billion in 2012, the global demand of heat exchangers will experience robust growth of about 7.8% annually over the next years. The market value is expected to reach US$57.9 billion by 2016 and to approach US$78.16 billion by 2020. Tubular heat exchangers and plate heat exchangers are still the most widely applied product types.[39]
A model of a simple heat exchanger[edit]
A simple heat exchange [40][41] might be thought of as two straight pipes with fluid flow, which are thermally connected. Let the pipes be of equal length L, carrying fluids with heat capacity C i {\displaystyle C_{i}} (energy per unit mass per unit change in temperature) and let the mass flow rate of the fluids through the pipes, both in the same direction, be j i {\displaystyle j_{i}} (mass per unit time), where the subscript i applies to pipe 1 or pipe 2.
Temperature profiles for the pipes are T 1 ( x ) {\displaystyle T_{1}(x)} and T 2 ( x ) {\displaystyle T_{2}(x)} where x is the distance along the pipe. Assume a steady state, so that the temperature profiles are not functions of time. Assume also that the only transfer of heat from a small volume of fluid in one pipe is to the fluid element in the other pipe at the same position, i.e., there is no transfer of heat along a pipe due to temperature differences in that pipe. By Newton's law of cooling the rate of change in energy of a small volume of fluid is proportional to the difference in temperatures between it and the corresponding element in the other pipe:
d u 1 d t = γ ( T 2 − T 1 ) {\displaystyle {\frac {du_{1}}{dt}}=\gamma (T_{2}-T_{1})}
d u 2 d t = γ ( T 1 − T 2 ) {\displaystyle {\frac {du_{2}}{dt}}=\gamma (T_{1}-T_{2})}
( this is for parallel flow in the same direction and opposite temperature gradients, but for counter-flow heat exchange countercurrent exchange the sign is opposite in the second equation in front of γ ( T 1 − T 2 ) {\displaystyle \gamma (T_{1}-T_{2})} )
, where u i ( x ) {\displaystyle u_{i}(x)} is the thermal energy per unit length and γ is the thermal connection constant per unit length between the two pipes. This change in internal energy results in a change in the temperature of the fluid element. The time rate of change for the fluid element being carried along by the flow is:
d u 1 d t = J 1 d T 1 d x {\displaystyle {\frac {du_{1}}{dt}}=J_{1}{\frac {dT_{1}}{dx}}}
d u 2 d t = J 2 d T 2 d x {\displaystyle {\frac {du_{2}}{dt}}=J_{2}{\frac {dT_{2}}{dx}}}
where J i = C i j i {\displaystyle J_{i}={C_{i}}{j_{i}}} is the "thermal mass flow rate". The differential equations governing the heat exchanger may now be written as:
J 1 ∂ T 1 ∂ x = γ ( T 2 − T 1 ) {\displaystyle J_{1}{\frac {\partial T_{1}}{\partial x}}=\gamma (T_{2}-T_{1})}
J 2 ∂ T 2 ∂ x = γ ( T 1 − T 2 ) . {\displaystyle J_{2}{\frac {\partial T_{2}}{\partial x}}=\gamma (T_{1}-T_{2}).}
Note that, since the system is in a steady state, there are no partial derivatives of temperature with respect to time, and since there is no heat transfer along the pipe, there are no second derivatives in x as is found in the heat equation. These two coupled first-order differential equations may be solved to yield:
T 1 = A − B k 1 k e − k x {\displaystyle T_{1}=A-{\frac {Bk_{1}}{k}}\,e^{-kx}}
T 2 = A + B k 2 k e − k x {\displaystyle T_{2}=A+{\frac {Bk_{2}}{k}}\,e^{-kx}}
where k 1 = γ / J 1 {\displaystyle k_{1}=\gamma /J_{1}} , k 2 = γ / J 2 {\displaystyle k_{2}=\gamma /J_{2}} ,
k = k 1 + k 2 {\displaystyle k=k_{1}+k_{2}}
(this is for parallel-flow, but for counter-flow the sign in front of k 2 {\displaystyle k_{2}} is negative, so that if k 2 = k 1 {\displaystyle k_{2}=k_{1}} , for the same "thermal mass flow rate" in both opposite directions, the gradient of temperature is constant and the temperatures linear in position x with a constant difference ( T 2 − T 1 ) {\displaystyle (T_{2}-T_{1})} along the exchanger, explaining why the counter current design countercurrent exchange is the most efficient )
and A and B are two as yet undetermined constants of integration. Let T 10 {\displaystyle T_{10}} and T 20 {\displaystyle T_{20}} be the temperatures at x=0 and let T 1 L {\displaystyle T_{1L}} and T 2 L {\displaystyle T_{2L}} be the temperatures at the end of the pipe at x=L. Define the average temperatures in each pipe as:
T ¯ 1 = 1 L ∫ 0 L T 1 ( x ) d x {\displaystyle {\overline {T}}_{1}={\frac {1}{L}}\int _{0}^{L}T_{1}(x)dx}
T ¯ 2 = 1 L ∫ 0 L T 2 ( x ) d x . {\displaystyle {\overline {T}}_{2}={\frac {1}{L}}\int _{0}^{L}T_{2}(x)dx.}
Using the solutions above, these temperatures are:
T 10 = A − B k 1 k {\displaystyle T_{10}=A-{\frac {Bk_{1}}{k}}} T 20 = A + B k 2 k {\displaystyle T_{20}=A+{\frac {Bk_{2}}{k}}}
T 1 L = A − B k 1 k e − k L {\displaystyle T_{1L}=A-{\frac {Bk_{1}}{k}}e^{-kL}} T 2 L = A + B k 2 k e − k L {\displaystyle T_{2L}=A+{\frac {Bk_{2}}{k}}e^{-kL}}
T ¯ 1 = A − B k 1 k 2 L ( 1 − e − k L ) {\displaystyle {\overline {T}}_{1}=A-{\frac {Bk_{1}}{k^{2}L}}(1-e^{-kL})} T ¯ 2 = A + B k 2 k 2 L ( 1 − e − k L ) . {\displaystyle {\overline {T}}_{2}=A+{\frac {Bk_{2}}{k^{2}L}}(1-e^{-kL}).}
Choosing any two of the temperatures above eliminates the constants of integration, letting us find the other four temperatures. We find the total energy transferred by integrating the expressions for the time rate of change of internal energy per unit length:
d U 1 d t = ∫ 0 L d u 1 d t d x = J 1 ( T 1 L − T 10 ) = γ L ( T ¯ 2 − T ¯ 1 ) {\displaystyle {\frac {dU_{1}}{dt}}=\int _{0}^{L}{\frac {du_{1}}{dt}}\,dx=J_{1}(T_{1L}-T_{10})=\gamma L({\overline {T}}_{2}-{\overline {T}}_{1})}
d U 2 d t = ∫ 0 L d u 2 d t d x = J 2 ( T 2 L − T 20 ) = γ L ( T ¯ 1 − T ¯ 2 ) . {\displaystyle {\frac {dU_{2}}{dt}}=\int _{0}^{L}{\frac {du_{2}}{dt}}\,dx=J_{2}(T_{2L}-T_{20})=\gamma L({\overline {T}}_{1}-{\overline {T}}_{2}).}
By the conservation of energy, the sum of the two energies is zero. The quantity T ¯ 2 − T ¯ 1 {\displaystyle {\overline {T}}_{2}-{\overline {T}}_{1}} is known as the Log mean temperature difference, and is a measure of the effectiveness of the heat exchanger in transferring heat energy.
See also[edit]
Architectural engineering
Chemical engineering
Cooling tower
Copper in heat exchangers
Heat pipe
Heat pump
Heat recovery ventilation
Jacketed vessel
Log mean temperature difference (LMTD)
Marine heat exchangers
Mechanical engineering
Micro heat exchanger
Moving bed heat exchanger
Packed bed and in particular Packed columns
Pumpable ice technology
Reboiler
Recuperator, or cross plate heat exchanger
Regenerator
Run around coil
Steam generator (nuclear power)
Surface condenser
Toroidal expansion joint
Thermosiphon
Thermal wheel, or rotary heat exchanger (including enthalpy wheel and desiccant wheel)
Waste heat
References[edit]
Jump up ^ Sadik Kakaç; Hongtan Liu (2002). Heat Exchangers: Selection, Rating and Thermal Design (2nd ed.). CRC Press. ISBN 0-8493-0902-6.
^ Jump up to: a b Saunders, E. A. (1988). Heat Exchanges: Selection, Design and Construction. New York: Longman Scientific and Technical.
Jump up ^ Industrial Shell-and-tube heat exchangers; American Industrial Heat Transfer Inc.; http://www.aihti.com/pdf/fbf.pdf
Jump up ^ Kister, Henry Z. (1992). Distillation Design (1st ed.). McGraw-Hill. ISBN 0-07-034909-6.
Jump up ^ Perry, Robert H.; Green, Don W. (1984). Perry's Chemical Engineers' Handbook (6th ed.). McGraw-Hill. ISBN 0-07-049479-7.
Jump up ^ Air Pollution Control Orientation Course from website of the Air Pollution Training Institute
Jump up ^ Energy savings in steam systems Archived 2007-09-27 at the Wayback Machine. Figure 3a, Layout of surface condenser (scroll to page 11 of 34 PDF pages)
Jump up ^ Coulson, J. & Richardson, J. (1983), Chemical Engineering – Design (SI Units), Volume 6, Pergamon Press, Oxford.
Jump up ^ Hewitt G, Shires G, Bott T (1994), Process Heat Transfer, CRC Press Inc, Florida.
Jump up ^ Table: Various Types of Gas – Liquid Direct Contact Heat Exchangers (Hewitt G, Shires G & Bott T, 1994)
Jump up ^ Kee Robert J.; et al. (2011). "The design, fabrication, and evaluation of a ceramic counter-flow microchannel heat exchanger". Applied Thermal Engineering. 31 (11): 2004–2012. doi:10.1016/j.applthermaleng.2011.03.009.
Jump up ^ Northcutt B.; Mudawar I. (2012). "Enhanced design of cross-flow microchannel heat exchanger module for high-performance aircraft gas turbine engines". Journal of Heat Transfer. 134 (6): 061801. doi:10.1115/1.4006037.
Jump up ^ Moallem E.; Padhmanabhan S.; Cremaschi L.; Fisher D. E. (2012). "Experimental investigation of the surface temperature and water retention effects on the frosting performance of a compact microchannel heat exchanger for heat pump systems". International journal of refrigeration. 35 (1): 171–186. doi:10.1016/j.ijrefrig.2011.08.010.
Jump up ^ Xu, B., Shi, J., Wang, Y., Chen, J., Li, F., & Li, D. (2014). Experimental Study of Fouling Performance of Air Conditioning System with Microchannel Heat Exchanger.
Jump up ^ MICROCHANNEL TECHNOLOGY Archived 2013-06-04 at the Wayback Machine.
Jump up ^ Patent 2,046,968 John C Raisley issued July 7, 1936; filed Jan. 8, 1934 [1]
^ Jump up to: a b c d Patil, Ramachandra K.; Shende, B.W.; Ghosh, Prasanfa K. (13 December 1982). "Designing a helical-coil heat exchanger". Chemical Engineering. 92 (24): 85–88. Retrieved 14 July 2015.
^ Jump up to: a b Haraburda, Scott S. (July 1995). "Three-Phase Flow? Consider Helical-Coil Heat Exchanger". Chemical Engineering. 102 (7): 149–151. Retrieved 14 July 2015.
Jump up ^ US 3805890, Boardman, Charles E. & John H. Germer, "Helical Coil Heat Exchanger", issued 1974
Jump up ^ Rennie, Timothy J. (2004). Numerical And Experimental Studies Of A Doublepipe Helical Heat Exchanger (PDF) (Ph.D.). Montreal: McGill University. pp. 3–4. Retrieved 14 July 2015.
Jump up ^ Korane, Ashok B.; Purandare, P.S.; Mali, K.V. (June 2012). "Heat Transfer Analysis Of Helical Coil Heat Exchanger With Circular And Square Coiled Pattern" (PDF). International Journal of Engineering & Science Research. 2 (6): 413–423. Retrieved 14 July 2015.
Jump up ^ Kuvadiya, Manish N.; Deshmukh, Gopal K.; Patel, Rankit A.; Bhoi, Ramesh H. (April 2015). "Parametric Analysis of Tube in Tube Helical Coil Heat Exchanger at Constant Wall Temperature" (PDF). International Journal of Engineering Research & Technology. 1 (10): 279–285. Retrieved 14 July 2015.
Jump up ^ Rennie, Timothy J.; Raghavan, Vijaya G.S. (September 2005). "Experimental studies of a double-pipe helical heat exchanger". Experimental Thermal and Fluid Science. 29 (8): 919–924. doi:10.1016/j.expthermflusci.2005.02.001. Retrieved 14 July 2015.
Jump up ^ Cooling Text
Jump up ^ E.A.D.Saunders (1988). Heat Exchangers:Selection Design And Construction Longman Scientific and Technical ISBN 0-582-49491-5
Jump up ^ Microgroove: The Microgroove advantage; http://www.microgroove.net/
Jump up ^ Q&A: Microchannel air-cooled condenser; Heatcraft Worldwide Refrigeration; April 2011; http://www.heatcraftrpd.com/landing/2011/air-cooled-condenser/res/pdfs/H-ACCMCX-QA.pdf
Jump up ^
White, F.M. ‘Heat and Mass Transfer’ © 1988 Addison-Wesley Publishing Co. pp. 602–604
Heat Exchangers Archived 2008-03-29 at the Wayback Machine. Kevin D. Rafferty, Gene Culver Geo-Heat Center, 1996–2001 Last Accessed 17/3/08
For manufacturing engineers who use heat processing equipment- Heat exchanger basics, BNP Media, 2007 Last Accessed 17/3/08
Jump up ^ I. A. Wiehe and R. J. Kennedy, Energy & Fuels, 14, 56 – 63 (2000).
Jump up ^ Panchal C;B; and Ebert W., Analysis of Exxon Crude-Oil-Slip-Stream Coking Data, Proc of Fouling Mitigation of Industrial Heat-Exchanger Equipment, San Luis Obispo, California, USA, p 451, June 1995
Jump up ^ Plate Heat Exchanger Cleaning Services AKS Heat Transfer. Retrieved 18 August 2017.
Jump up ^ Heat Loss from the Respiratory Tract in Cold, Defense Technical Information Center, April 1955
Jump up ^ Randall, David J.; Warren W. Burggren; Kathleen French; Roger Eckert (2002). Eckert animal physiology: mechanisms and adaptations. Macmillan. p. 587. ISBN 0-7167-3863-5.
Jump up ^ [2]
Jump up ^ Heyning and Mead; Mead, JG (November 1997). "Thermoregulation in the Mouths of Feeding Gray Whales". Science. 278 (5340): 1138–1140. doi:10.1126/science.278.5340.1138. PMID 9353198. Retrieved 2010-01-19.
Jump up ^ Carotid rete cools brain: Thomson's gazelle -- AskNature
Jump up ^ "United States Patent 4498525, Fuel/oil heat exchange system for an engine". United States Patent and Trademark Office. Retrieved 3 February 2009.
Jump up ^ "Boeing links Heathrow, Atlanta Trent 895 engine rollbacks". FlightGlobal.com. Retrieved 3 February 2009.
Jump up ^ "Market Report: Global Heat Exchanger Market". Acmite Market Intelligence. External link in |publisher= (help)
Jump up ^ Kay J M & Nedderman R M (1985) Fluid Mechanics and Transfer Processes, Cambridge University Press
Jump up ^ "MIT web course on Heat Exchangers". [MIT].
Coulson, J. and Richardson, J (1999). Chemical Engineering- Fluid Flow. Heat Transfer and Mass Transfer- Volume 1; Reed Educational & Professional Publishing LTD
Dogan Eryener (2005), ‘Thermoeconomic optimization of baffle spacing for shell and tube heat exchangers’, Energy Conservation and Management, Volume 47, Issue 11–12, Pages 1478–1489.
G.F.Hewitt, G.L.Shires, T.R.Bott (1994) Process Heat Transfer, CRC Press, Inc, United States Of America.
List of Indian Heat Exchanger Manufacturing companies http://www.indiantradestreet.com/air-compressor-heat-exchanger.html
External links[edit]
Wikimedia Commons has media related to Heat exchangers.
Heat Exchangers at Curlie (based on DMOZ)
Shell and Tube Heat Exchanger Design Software for Educational Applications (PDF)
Plate Heat Exchanger Maintenance
EU Pressure Equipment Guideline
A Thermal Management Concept For More Electric Aircraft Power System Application (PDF)
Authority control
NDL: 00568133
Retrieved from "https://en.wikipedia.org/w/index.php?title=Heat_exchanger&oldid=828277367"
Categories:
Heat exchangers
Heat transfer
Gas technologies
Hidden categories:
Webarchive template wayback links
CS1 errors: external links
Articles needing additional references from March 2017
All articles needing additional references
All articles with unsourced statements
Articles with unsourced statements from June 2013
Articles with unsourced statements from April 2008
Pages using div col with deprecated parameters
Articles with Curlie links
Navigation menu
Personal tools
Not logged in
Talk
Contributions
Create account
Log in
Namespaces
Article
Talk
Variants
Views
Read
Edit
View history
More
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Wikipedia store
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact page
Tools
What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Wikidata item
Cite this page
Print/export
Create a book
Download as PDF
Printable version
In other projects
Wikimedia Commons
Languages
Afrikaans
العربية
Български
Bosanski
Català
Čeština
Dansk
Deutsch
Eesti
Ελληνικά
Español
Esperanto
فارسی
Français
Galego
한국어
Հայերեն
हिन्दी
Hrvatski
Ido
Bahasa Indonesia
Italiano
עברית
Қазақша
Latviešu
Nederlands
日本語
Norsk
Norsk nynorsk
پښتو
Polski
Português
Română
Русский
Simple English
Српски / srpski
Srpskohrvatski / српскохрватски
Suomi
Svenska
தமிழ்
ไทย
Türkçe
Українська
Tiếng Việt
中文
36 more
Edit links
This page was last edited on 1 March 2018, at 16:37.
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.
Privacy policy
About Wikipedia
Disclaimers
Contact Wikipedia
Developers
Cookie statement
Mobile view
Enable previews

values: mw-page-base noprint

values: mw-head-base noprint

values: firstHeading firstHeading en

values: siteSub noprint

values: jump-to-nav mw-jump

attrs: href class title

value: b

value: sup

values:
/wiki/Space_heating
mw-redirect
Space heating

values:
/wiki/Engine_coolant
mw-redirect
Engine coolant

values:
gallery mw-gallery-traditional
float:right; margin:0.5em 0 0.5em 1em

values:
/wiki/Log_mean_temperature_difference
mw-redirect
Log mean temperature difference

values: Edit section: Shell and tube heat exchanger

values:
/wiki/Baffle_(heat_exchanger)
mw-redirect
Baffle (heat exchanger)

values: Edit section: Plate and shell heat exchanger

values: Edit section: Adiabatic wheel heat exchanger

values: Edit section: Pillow plate heat exchanger

values: Help:Introduction to referencing with Wiki Markup/1

values: plainlinks metadata ambox ambox-content ambox-Unreferenced

values: Edit section: Dynamic scraped surface heat exchanger

values: Edit section: Phase-change heat exchangers

values:
/wiki/Petroleum_refinery
mw-redirect
Petroleum refinery

values:
/wiki/Power_plant
mw-redirect
Power plant

values: Edit section: Direct contact heat exchangers

values: Edit section: Microchannel heat exchangers

values:
/wiki/Microchannel_heat_exchanger
mw-redirect
Microchannel heat exchanger

values:
/wiki/Gas_turbine_engines
mw-redirect
Gas turbine engines

values: Edit section: Helical-coil heat exchangers

values:
/wiki/Scott_S._Haraburda
mw-redirect
Scott S. Haraburda

values:
/wiki/Liquid_metal_fast_breeder_reactor
mw-redirect
Liquid metal fast breeder reactor

values: Charles E. Boardman (page does not exist)

values: Ramachandra K. Patil (page does not exist)

values:
noprint Inline-Template Template-Fact
white-space:nowrap;

values:
/wiki/Pressure_washer
mw-redirect
Pressure washer

values: This claim needs references to reliable sources. (April 2008)

values:
/wiki/Nickel_alloys
mw-redirect
Nickel alloys

values:
/wiki/Copper_MicroGroove
mw-redirect
Copper MicroGroove

values: Edit section: Monitoring and maintenance

values:
/wiki/Pampiniform_plexus
mw-redirect
Pampiniform plexus

values: Edit section: Birds, fish, marine mammals

values:
/wiki/Marine_mammals
mw-redirect
Marine mammals

values:
/wiki/Waste_water_treatment
mw-redirect
Waste water treatment

values:
/wiki/Petroleum_refining
mw-redirect
Petroleum refining

values:
/wiki/Anaerobic_digester
mw-redirect
Anaerobic digester

values: Edit section: Current market and forecast

values: Edit section: A model of a simple heat exchanger

values: vertical-align: -0.671ex; width:2.461ex; height:2.509ex;

values: vertical-align: -0.671ex; margin-left: -0.027ex; width:1.784ex; height:2.509ex;

values: vertical-align: -0.838ex; width:5.551ex; height:2.843ex;

values: vertical-align: -2.005ex; width:18.27ex; height:5.509ex;

values: vertical-align: -0.838ex; width:10.736ex; height:2.843ex;

values: vertical-align: -0.838ex; width:5.268ex; height:2.843ex;

values: vertical-align: -2.005ex; width:14.343ex; height:5.509ex;

values: vertical-align: -0.671ex; width:9.408ex; height:2.509ex;

values: vertical-align: -2.005ex; width:20.745ex; height:5.509ex;

values: vertical-align: -2.005ex; width:21.391ex; height:5.509ex;

values: vertical-align: -2.005ex; width:19.737ex; height:5.509ex;

values: vertical-align: -0.838ex; width:10.133ex; height:2.843ex;

values: vertical-align: -0.671ex; width:11.681ex; height:2.509ex;

values: vertical-align: -0.671ex; width:2.265ex; height:2.509ex;

values: vertical-align: -0.671ex; width:7.629ex; height:2.509ex;

values: vertical-align: -0.838ex; width:9.473ex; height:2.843ex;

values: vertical-align: -0.671ex; width:3.234ex; height:2.509ex;

values: vertical-align: -0.671ex; width:3.531ex; height:2.509ex;

values: vertical-align: -2.338ex; width:21.19ex; height:6.176ex;

values: vertical-align: -2.338ex; width:21.837ex; height:6.176ex;

values: vertical-align: -2.005ex; width:15.781ex; height:5.509ex;

values: vertical-align: -2.005ex; width:20.649ex; height:5.509ex;

values: vertical-align: -2.171ex; width:25.916ex; height:5.676ex;

values: vertical-align: -2.171ex; width:26.563ex; height:5.676ex;

values: vertical-align: -2.338ex; width:52.788ex; height:6.176ex;

values: vertical-align: -2.338ex; width:53.434ex; height:6.176ex;

values: {\displaystyle {\overline {T}}_{2}-{\overline {T}}_{1}}

values: vertical-align: -0.671ex; width:8.814ex; height:3.343ex;

values:
/wiki/Run_around_coil
mw-redirect
Run around coil

values: -moz-column-width: 25em; -webkit-column-width: 25em; column-width: 25em;

values:
nofollow
external free
http://www.aihti.com/pdf/fbf.pdf

values:
nofollow
external text
//doi.org/10.1115%2F1.4006037

values:
nofollow
http://www.microgroove.net/
external free

values:
nofollow
external text
http://www.process-heating.com

values:
nofollow
external text
http://aksheattransfer.com/plate.html

values:
/wiki/PubMed_Identifier
mw-redirect
PubMed Identifier

values:
nofollow
external text
//www.ncbi.nlm.nih.gov/pubmed/9353198

values:
nofollow
external text
http://www.acmite.com

values: -moz-column-width: 30em; -webkit-column-width: 30em; column-width: 30em; list-style-type: decimal;

values: Category:Webarchive template wayback links

values: Category:Articles needing additional references from March 2017

values: Category:All articles needing additional references

values: Category:All articles with unsourced statements

values: Category:Articles with unsourced statements from June 2013

values: Category:Articles with unsourced statements from April 2008

values: Category:Pages using div col with deprecated parameters

values: Discussion about edits from this IP address [ctrl-alt-n]

values: A list of edits made from this IP address [ctrl-alt-y]

values: You are encouraged to create an account and log in; however, it is not mandatory

values: You're encouraged to log in; however, it's not mandatory. [ctrl-alt-o]

values:
/wiki/Heat_exchanger
View the content page [ctrl-alt-c]
c

values: Discussion about the content page [ctrl-alt-t]

values: p-namespaces navigation vectorTabs p-namespaces-label

values:
p-variants
navigation
vectorMenu emptyPortlet
p-variants-label

values: Past revisions of this page [ctrl-alt-h]

values: p-views navigation vectorTabs p-views-label

values:
p-cactions
navigation
vectorMenu emptyPortlet
p-cactions-label

values:
mw-wiki-logo
/wiki/Main_Page
Visit the main page

values:
/wiki/Main_Page
Visit the main page [ctrl-alt-z]
z

values: portal navigation p-wikibase-otherprojects p-wikibase-otherprojects-label

values:
interlanguage-link interwiki-af
display: none;

values: مبادل حراري – Arabic

values: Топлообменник – Bulgarian

values:
interlanguage-link interwiki-bg
display: none;

values:
interlanguage-link interwiki-bs
display: none;

values:
interlanguage-link interwiki-ca
display: none;

values:
interlanguage-link interwiki-cs
display: none;

values:
interlanguage-link interwiki-da
display: none;

values:
interlanguage-link interwiki-de
display: none;

values:
interlanguage-link interwiki-et
display: none;

values: Εναλλάκτης θερμότητας – Greek

values:
interlanguage-link interwiki-el
display: none;

values:
interlanguage-link interwiki-eo
display: none;

values: مبدل گرمایی – Persian

values:
interlanguage-link interwiki-fa
display: none;

values:
interlanguage-link interwiki-gl
display: none;

values:
interlanguage-link interwiki-ko
display: none;

values: Ջերմափոխանակիչ ապարատ – Armenian

values:
interlanguage-link interwiki-hy
display: none;

values: ऊष्मा विनिमायक – Hindi

values:
interlanguage-link interwiki-hr
display: none;

values:
interlanguage-link interwiki-io
display: none;

values:
interlanguage-link interwiki-it
display: none;

values: מחלף חום – Hebrew

values:
interlanguage-link interwiki-he
display: none;

values: Жылу алмастырғыш – Kazakh

values:
interlanguage-link interwiki-kk
display: none;

values:
interlanguage-link interwiki-lv
display: none;

values:
interlanguage-link interwiki-nl
display: none;

values:
interlanguage-link interwiki-ja
display: none;

values:
interlanguage-link interwiki-no
display: none;

values:
interlanguage-link interwiki-nn
display: none;

values: تودوخه بدلونکی – Pashto

values:
interlanguage-link interwiki-ps
display: none;

values:
interlanguage-link interwiki-pl
display: none;

values: Trocador de energia térmica – Portuguese

values: interlanguage-link interwiki-ro badge-Q17437796 badge-featuredarticle

values: Теплообменник – Russian

values:
interlanguage-link interwiki-simple
display: none;

values:
interlanguage-link interwiki-sr
display: none;

values:
interlanguage-link interwiki-sh
display: none;

values:
interlanguage-link interwiki-fi
display: none;

values:
interlanguage-link interwiki-sv
display: none;

values: வெப்பப் பரிமாற்றி – Tamil

values:
interlanguage-link interwiki-ta
display: none;

values: เครื่องแลกเปลี่ยนความร้อน – Thai

values:
interlanguage-link interwiki-th
display: none;

values:
interlanguage-link interwiki-tr
display: none;

values: Теплообмінний апарат – Ukrainian

values:
interlanguage-link interwiki-uk
display: none;

values:
interlanguage-link interwiki-vi
display: none;

values: All languages (initial selection from common choices by you and others)

values: /static/images/wikimedia-button-1.5x.png 1.5x, /static/images/wikimedia-button-2x.png 2x

values: /static/images/poweredby_mediawiki_132x47.png 1.5x, /static/images/poweredby_mediawiki_176x62.png 2x

values:
suggestions
display: none; font-size: 13px;

values: mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-Heat_exchanger rootpage-Heat_exchanger skin-vector action-view


text:
New College Worcester
From Wikipedia, the free encyclopedia
Jump to: navigation, search
New College Worcester
Established
1866 (1866)
Type
Non-maintained special school
Headteacher
Nicky Ross
Location
Whittington Road
Worcester
Worcestershire
WR5 2JX
England
52°19′58″N 2°04′00″W / 52.332684°N 2.066728°W / 52.332684; -2.066728Coordinates: 52°19′58″N 2°04′00″W / 52.332684°N 2.066728°W / 52.332684; -2.066728
DfE URN
117064 Tables
Ofsted
Reports
Gender
Coeducational
Ages
11–19
Website
newcollegeworcester.co.uk
New College Worcester (or NCW; formerly RNIB New College) is an independent boarding and day school for students, aged 11–19, who are blind or partially sighted. It caters for around 80 students. It is located in the city of Worcester, England. A 2012 Ofsted inspection classed the school with a Grade 2 (Good).[1] The school has also been featured in the Good Schools Guide.[citation needed]
Contents
[hide]
1 History
2 Curriculum
3 Accommodation
4 Affiliations
5 Media
6 Associated people and alumni
7 See also
8 References
9 Further reading
10 External links
History[edit]
In 1866 a special needs boarding school was established as Worcester College for the Blind Sons of Gentlemen, based first at The Commandery,[2] the former English Civil War headquarters of King Charles II. In 1887, following a purchase of land by Eliza Warrington, Worcester College relocated to the village of Powick, then moving to its present location in Whittington Road, Worcester in 1902.[2] New buildings were added in the 1930s, including the Baldwin wing, which included extra classrooms, dormitories, a gymnasium, and study rooms for fifth and sixth form students. In 1936, the British and Foreign Blind Association (which later became the RNIB) took over all financial responsibility for the school, until 2007 when NCW split from the RNIB.[2] In 1944, an Act of Parliament (the Education Act 1944) recognised the establishment as an official grammar school for blind boys.[2]
During the 1950s much construction work was undertaken at the Whittington Road site, including the building of an open-air swimming pool and a chapel, as well as major extension work (adding the science block to the main building). A second wing, opened by Princess Margaret in 1962 provided facilities for a new science laboratory and a craft and woodwork shop. A new chapel had been built at the same time. In the 1970s, the School's guest house, Fletcher, was purchased. This house has also been used as additional accommodation of CSVs (Community Service Volunteers) and its garden has in the past been developed for gardening.
The most extensive construction work took place in the 1980s following the merger with Chorleywood College for Girls with Little or No Sight. Around 2000 the new Learning Resources Centre (LRC) was opened adjoining the chapel and mathematics corridor - as well as giving a new school a production venue and computer resources. The LRC replaced the former library, which became the offices of the Senior Management Team (SMT). In 1987, Chorleywood College for Girls and Worcester College for the Blind closed. The two former establishments merged, taking up residence at Worcester College's site which was renamed RNIB New College Worcester and became coeducational.[2]
In 2007, funding issues resulted in negotiations between the governors of the college and the RNIB, reaching a consensus that enabled the college to become an independent non-maintained special school,[2] although it continues to collaborate with the RNIB to the benefit of visually impaired children and young people. The school was renamed New College Worcester and given a new logo.
In 2007 the college received an outstanding OFSTED report and was awarded specialist special school status, enabling it to continuously improve the support for its students.[3] In 2008 OFSTED concluded that students at New College Worcester receive high quality care and education.[4]
Curriculum[edit]
The school offers a wide range of subjects and courses at all academic levels based on the National Curriculum. At Key Stage 3 subjects include mathematics, English, science, history, geography, religious studies, Information Communication Technology (ICT), music, and drama. Courses provided at Advanced Level academic studies (AS and A2 levels) include biology, business studies, chemistry, computing, critical thinking, drama & theatre studies, English literature & language, French, geography, German, government & politics, health & social care, history, law, Latin, mathematics, music, music technology, philosophy, physics, Religious Studies, psychology, sociology, and sport & PE, New College also provides additional subjects including language courses for Japanese and Spanish, and training in cookery and domestic skills. It also offers repeat GCSEs, ASDAN, adult literacy and numeracy, work placements and courses at a local College in Worcester.
Students learn to become independent through mobility lessons with the school's mobility training officers, as well as basic living skills sessions in school (Independent Living Skills; formerly known as 'Design For Living', or 'DFL') and in student accommodation. New College will also teach Braille to students if necessary.
A large staff enables a teacher:student ratio of between 3 and 4 students per teacher.[5] Among the teaching aids in use at the school is a series of MP3 recordings of core textbook material. The MP3s were developed by the schools science department and they are available on the school's Intranet.[6]
Accommodation[edit]
Boarding accommodation is provided at the school, in four main houses for the lower school, with a house and hostel for the Sixth Form. The four lower school houses (Brown, Bradnack, Peggy Markes and Dorothy McHugh), the Sixth Form buildings (the Phyllis Monk House and the Phyllis Monk Hostel) and school guest house (Fletcher) are named after former headmasters of New College.
Affiliations[edit]
New College has two 'sister schools'. One, in France, is the Royal Institution for Blind Youth in Paris, where Braille inventor Louis Braille was a student, and a school for the blind in Marburg, Germany. Exchanges and trips are arranged between the three. New College also enjoys close relations with Malvern Girls College.
Media[edit]
NCW was featured in an episode of Challenge Anneka. In the show, presenter Anneka Rice's team produced the world's first multi-sensory maze for mobility training. The maze involved a series of environments and challenges for blind and partially sighted people. They included a "Pelican crossing", bridges, an observation tower with a spiral staircase, concrete pipe and corrugated iron tunnels, a scaffolding alley, a telephone box and post box, half a car fixed to a wall (giving an impression of a parked car) and a space exploration sculpture created by visually impaired artist Peter Tait. The programme was broadcast in the popular television series during RNIB Week on 18 September 1993.
Associated people and alumni[edit]
Peter White, BBC Radio presenter[7]
Reginald Walter Bonham, most famous British blind chess player ever and six times world champion[8]
Gary O'Donoghue, political reporter for BBC News[9]
Rupert Cross, former Vinerian Professor of English Law, University of Oxford
John Wall, first visually impaired judge of the High Court of Justice
Colin Low, Chairman of the RNIB and member of the House of Lords
John Foster Wilson, founder of the Royal Commonwealth Society for the Blind
Edward Elgar, composer, held professorial posts at Worcester in an early period of his career
David Clarke (Paralympian Footballer), Paralympian Blind Football
According to a biography written by Stephen Pollard, former blind British Cabinet Minister David Blunkett MP failed on his assessment to enter the school as a student.[10]
See also[edit]
Exhall Grange School
Jordanstown Schools
Royal Blind School
References[edit]
Jump up ^ Ofsted report June 2012 Retrieved 20 January 2016
^ Jump up to: a b c d e f Jones, Sally (20 May 2008). "Taking our college on its own was best move". Hereford Times. Retrieved 22 January 2010.
Jump up ^ "Blunkett inspires at college's speech day". Hereford Times. 9 July 2007. Retrieved 22 January 2010.
Jump up ^ Jones, Sally (11 January 2008). "College care of blind students is outstanding". Hereford Times. Retrieved 22 January 2010.
Jump up ^ Guide to Independent Schools Retrieved 27 July 2009
Jump up ^ Excellence Gateway Retrieved 27 July 2009
Jump up ^ White, Peter See it My Way Warner ISBN 0-7515-2547-2
Jump up ^ BrailleChess.org Retrieved 27 July 2009
Jump up ^ "BBC - Ouch! (disability) - Interviews - 13 Questions: Gary O'Donoghue". BBC. Retrieved 26 February 2010.
Jump up ^ Stephen Pollard, Stephen (2004) David Blunkett Hodder & Stoughton ISBN 978-0-340-82534-1
Further reading[edit]
Bell, Donald An experiment in education: The history of Worcester College for the Blind, 1866-1966 (ASIN B0000CNE5K)
Fletcher, Richard C., The College on the Ridge (ISBN 0950988103)
British Journal of Visual Impairment (Vol. 9, No. 3, 83-85 (1991) doi:10.1177/026461969100900305
External links[edit]
New College's official site
OFSTED site for RNIB New College
Details New College's earlier time at the Commandery
Prisoner 4099 - an example of student activities at New College
isbiSchools New College Worcester page
[show]
v
t
e
Schools in Worcestershire
Primary
Holy Trinity School
Middle
Alvechurch CE Middle School
Aston Fields Middle School
Bredon Hill Middle School
Ridgeway Middle School
St John's CE Middle School Academy
Secondary
Baxter College
The Bewdley School
Bishop Perowne CE College
Blessed Edward Oldcorne RC College
The Chantry School
The Chase School
Christopher Whitehead Language College
The De Montfort School
Droitwich Spa High School
Dyson Perrins CE Academy
Elgar Technology College
Hagley RC High School
Hanley Castle High School
Haybridge High School
Holy Trinity School
King Charles I School
North Bromsgrove High School
Nunnery Wood High School
Pershore High School
Prince Henry's High School
RSA Academy Arrow Vale
St Augustine's High School
South Bromsgrove High School
The Stourport High School
Tenbury High Ormiston Academy
Trinity High School
Tudor Grange Redditch
Tudor Grange Worcester
Waseley Hills High School
Wolverley CE Secondary School
Woodrush High School
Special
New College Worcester
Sunfield Children's Home
Vale of Evesham School
Wyre Forest School
Independent
Abberley Hall School
Abbey College
Bowbrook House School
Bredon School
Bromsgrove School
Dodderhill School
Heathfield School
The King's School
Malvern College
Malvern St James
River School
Royal Grammar School Worcester
St Michael's College
Further education colleges
Heart of Worcestershire College
South Worcestershire College
Former
Elgar Technology College
Greyfriars, Worcester
Hillside School
St Mary's School
[show]
v
t
e
Organisations for visually impaired people in the United Kingdom
Charities
Action for Blind People
Blind in Business
BlindArt
Bradbury Fields
British Blind Sport
Cardiff Institute for the Blind
Fight for Sight
Galloway's Society for the Blind
The Guide Dogs for the Blind Association
Henshaws Society for Blind People
Kent Association for the Blind
Leeds Society for Deaf and Blind People
Listening Books
Nalsvi
National Library for the Blind
Royal London Society for the Blind
RNIB
Blind Veterans UK
SeeAbility, The Royal School for the Blind
Sightsavers
SITE
Vista
Warwickshire Vision Support
Assistive technology
Dolphin Computer Access
Leisure
Traveleyes
Media
Insight Radio
Schools and colleges
Dorton House
Exhall Grange School
Jordanstown Schools
Joseph Clarke School
Linden Lodge School
New College Worcester
Queen Alexandra College
RNIB College, Loughborough
RNIB Pears Centre for Specialist Learning
Royal Blind School
Royal National College for the Blind
Royal School for the Blind (Liverpool)
Retrieved from "https://en.wikipedia.org/w/index.php?title=New_College_Worcester&oldid=787322006"
Categories:
Educational institutions established in 1866
Schools for the blind in the United Kingdom
Special schools in Worcestershire
1866 establishments in England
Independent schools in Worcestershire
Hidden categories:
Coordinates on Wikidata
Pages using infobox UK school with unknown parameters
All articles with unsourced statements
Articles with unsourced statements from January 2016
Navigation menu
Personal tools
Not logged in
Talk
Contributions
Create account
Log in
Namespaces
Article
Talk
Variants
Views
Read
Edit
View history
More
Search
Navigation
Main page
Contents
Featured content
Current events
Random article
Donate to Wikipedia
Wikipedia store
Interaction
Help
About Wikipedia
Community portal
Recent changes
Contact page
Tools
What links here
Related changes
Upload file
Special pages
Permanent link
Page information
Wikidata item
Cite this page
Print/export
Create a book
Download as PDF
Printable version
Languages
Français
Edit links
This page was last edited on 24 June 2017, at 18:56.
Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.
Privacy policy
About Wikipedia
Disclaimers
Contact Wikipedia
Developers
Cookie statement
Mobile view
Enable previews

key: html

type: local

value: div

attrs: id class

values: mw-page-base noprint

values: mw-head-base noprint

value: a

attrs: id class lang

values: firstHeading firstHeading en

values: siteSub noprint

values: jump-to-nav mw-jump

value: caption

value: img

attrs: alt src width height srcset data-file-width data-file-height

attrs: href class

value: td

attrs: colspan style

value: tr

value: th

value: span

values:
/wiki/Special_school
mw-redirect
Special school

values: Maps, aerial photos, and other data for this location

values:
nofollow
http://www.newcollegeworcester.co.uk/
external text

values:
/wiki/Partially_sighted
mw-redirect
Partially sighted

values: This claim needs references to reliable sources. (January 2016)

values:
noprint Inline-Template Template-Fact
white-space:nowrap;

values: Royal National Institute of Blind People

values:
/wiki/Princess_Margaret
mw-redirect
Princess Margaret

values: Senior Management Team (page does not exist)

values: Office for Standards in Education, Children's Services and Skills

values:
/wiki/Advanced_Level_(UK)
mw-redirect
Advanced Level (UK)

values:
/wiki/Royal_Institution_for_Blind_Youth
mw-redirect
Royal Institution for Blind Youth

values: Edit section: Associated people and alumni

values:
/wiki/Reginald_Walter_Bonham
mw-redirect
Reginald Walter Bonham

values:
/wiki/John_Foster_Wilson
mw-redirect
John Foster Wilson

values: Royal Commonwealth Society for the Blind

values: David Clarke (Paralympian Footballer) (page does not exist)

values:
/wiki/Cabinet_Minister
mw-redirect
Cabinet Minister

values:
/wiki/Member_of_Parliament
mw-redirect
Member of Parliament

values:
reflist mw-references-wrap
list-style-type: decimal;

values: Alvechurch Church of England Middle School

values:
/wiki/Aston_Fields_Middle_School
mw-redirect
Aston Fields Middle School

values:
/wiki/Bredon_Hill_Middle_School
mw-redirect
Bredon Hill Middle School

values:
/wiki/Ridgeway_Middle_School
mw-redirect
Ridgeway Middle School

values: St John's Church of England Middle School Academy

values: The Bewdley School and Sixth Form Centre

values: Bishop Perowne Church of England College

values: Blessed Edward Oldcorne Catholic College

values:
/wiki/Hagley_RC_High_School
mw-redirect
Hagley RC High School

values: The Stourport High School and Sixth Form Centre

values: Trinity High School and Sixth Form Centre

values: Waseley Hills High School and Sixth Form Centre

values:
/wiki/Wolverley_C_E_Secondary_School
mw-redirect
Wolverley C E Secondary School

values:
/wiki/The_King%27s_School,_Worcester
mw-redirect
The King's School, Worcester

values:
/wiki/South_Worcestershire_College
mw-redirect
South Worcestershire College

values: nowraplinks collapsible autocollapse navbox-inner

values: Template:Organizations for visually impaired people in the United Kingdom

values: Template talk:Organizations for visually impaired people in the United Kingdom

values: The Guide Dogs for the Blind Association

values: SeeAbility, The Royal School for the Blind (page does not exist)

values: Supported Integration Training and Employment (SITE)

values: Vista, The Royal Leicester, Leicestershire and Rutland Society for the Blind

values:
/wiki/Insight_Radio
mw-redirect
Insight Radio

values: RNIB Pears Centre for Specialist Learning

values: Category:Educational institutions established in 1866

values: Category:Schools for the blind in the United Kingdom

values: Category:Special schools in Worcestershire

values: Category:Independent schools in Worcestershire

values: Category:Pages using infobox UK school with unknown parameters

values: Category:All articles with unsourced statements

values: Category:Articles with unsourced statements from January 2016

values: Discussion about edits from this IP address [ctrl-alt-n]

values: A list of edits made from this IP address [ctrl-alt-y]

values: You are encouraged to create an account and log in; however, it is not mandatory

values: You're encouraged to log in; however, it's not mandatory. [ctrl-alt-o]

values:
/wiki/New_College_Worcester
View the content page [ctrl-alt-c]
c

values: Discussion about the content page [ctrl-alt-t]

values: p-namespaces navigation vectorTabs p-namespaces-label

values:
p-variants
navigation
vectorMenu emptyPortlet
p-variants-label

values: Past revisions of this page [ctrl-alt-h]

values: p-views navigation vectorTabs p-views-label

values:
p-cactions
navigation
vectorMenu emptyPortlet
p-cactions-label

values:
mw-wiki-logo
/wiki/Main_Page
Visit the main page

values:
/wiki/Main_Page
Visit the main page [ctrl-alt-z]
z

values: Featured content – the best of Wikipedia

values: Find background information on current events

values:
/wiki/Special:Random
Load a random article [ctrl-alt-x]
x

values: portal navigation p-navigation p-navigation-label

values: Guidance on how to use and edit Wikipedia

values: About the project, what you can do, where to find things

values: A list of recent changes in the wiki [ctrl-alt-r]

values: portal navigation p-interaction p-interaction-label

values: List of all English Wikipedia pages containing links to this page [ctrl-alt-j]

values: Recent changes in pages linked from this page [ctrl-alt-k]

values:
/wiki/Wikipedia:File_Upload_Wizard
Upload files [ctrl-alt-u]
u

values: A list of all special pages [ctrl-alt-q]

values: Permanent link to this revision of the page

values: Link to connected data repository item [ctrl-alt-g]

values: Printable version of this page [ctrl-alt-p]

values: mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject page-New_College_Worcester rootpage-New_College_Worcester skin-vector action-view