03-07-2012, 04:04 PM
heat exchanger
A heat exchanger is an equipment or device built for efficient heat transfer from one medium to another, whether the media are separated by a solid wall so that they never mix, or the media are in direct contact. Heat exchanger are widely used in refrigeration, space heating, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, and natural gas processing. A common example of a heat exchanger is the radiator in a car, in which the heat source, being a hot engine-cooling fluid, water, transfers heat to air flowing through the radiator.
In industry, specifically process or manufacturing plants there are other types of heat exchanger such as plate heat exchangers, spiral heat exchangers and shell and tube heat exchangers. All of these heat exchangers are special and have their dedicated purpose or function when being employed. The price, size, specification, purpose and design varies within each other.
Heat exchanger must be properly maintained in order for it to be working efficiently and effectively. Energy is being transferred from one side to the other, thus it acts like an energy saver. When the heat exchanger is no longer efficiently transferring heat, it is time for cleaning. Hence, the heat exchanger will be stopped and cleaned from scale sticking on the surface of the wall. Failing to clean the heat exchanger will result to tremendous lost of energ
Introduction
A heat exchanger is a device that is used for transfer of thermal energy (enthalpy)between two or more fluids, between a solid surface and a fluid, or between solidparticulates and a fluid, at differing temperatures and in thermal contact, usually withoutexternal heat and work interactions. The fluids may be single compounds or mixtures.Typical applications involve heating or cooling of a fluid stream of concern, evaporation orcondensation of a single or multicomponent fluid stream, and heat recovery or heatrejection from a system. In other applications, the objective may be to sterilize, pasteurize,fractionate, distill, concentrate, crystallize, or control process fluid. In some heatexchangers, the fluids exchanging heat are in direct contact. In other heat exchangers, heattransfer between fluids takes place through a separating wall or into and out of a wall in atransient manner.In most heat exchangers, the fluids are separated by a heat transfer surface, andideally they do not mix. Such exchangers are referred to as the
direct transfer type,
orsimply
recuperators.
In contrast, exchangers in which there is an intermittent heatexchange between the hot and cold fluids via thermal energy storage and rejection throughthe exchanger surface or matrix—are referred to as the
indirect transfer type
or
storagetype,
or simply
regenerators.
Such exchangers usually have leakage and fluid carryover fromone stream to the other.Heat exchangers may be classified according to transfer process, construction, flowarrangement, surface compactness, number of fluids and heat transfer mechanisms oraccording to process functions
A heat exchanger is an equipment or device built for efficient heat transfer from one medium to another, whether the media are separated by a solid wall so that they never mix, or the media are in direct contact. Heat exchanger are widely used in refrigeration, space heating, air conditioning, power plants, chemical plants, petrochemical plants, petroleum refineries, and natural gas processing. A common example of a heat exchanger is the radiator in a car, in which the heat source, being a hot engine-cooling fluid, water, transfers heat to air flowing through the radiator.
In industry, specifically process or manufacturing plants there are other types of heat exchanger such as plate heat exchangers, spiral heat exchangers and shell and tube heat exchangers. All of these heat exchangers are special and have their dedicated purpose or function when being employed. The price, size, specification, purpose and design varies within each other.
Heat exchanger must be properly maintained in order for it to be working efficiently and effectively. Energy is being transferred from one side to the other, thus it acts like an energy saver. When the heat exchanger is no longer efficiently transferring heat, it is time for cleaning. Hence, the heat exchanger will be stopped and cleaned from scale sticking on the surface of the wall. Failing to clean the heat exchanger will result to tremendous lost of energ
Introduction
A heat exchanger is a device that is used for transfer of thermal energy (enthalpy)between two or more fluids, between a solid surface and a fluid, or between solidparticulates and a fluid, at differing temperatures and in thermal contact, usually withoutexternal heat and work interactions. The fluids may be single compounds or mixtures.Typical applications involve heating or cooling of a fluid stream of concern, evaporation orcondensation of a single or multicomponent fluid stream, and heat recovery or heatrejection from a system. In other applications, the objective may be to sterilize, pasteurize,fractionate, distill, concentrate, crystallize, or control process fluid. In some heatexchangers, the fluids exchanging heat are in direct contact. In other heat exchangers, heattransfer between fluids takes place through a separating wall or into and out of a wall in atransient manner.In most heat exchangers, the fluids are separated by a heat transfer surface, andideally they do not mix. Such exchangers are referred to as the
direct transfer type,
orsimply
recuperators.
In contrast, exchangers in which there is an intermittent heatexchange between the hot and cold fluids via thermal energy storage and rejection throughthe exchanger surface or matrix—are referred to as the
indirect transfer type
or
storagetype,
or simply
regenerators.
Such exchangers usually have leakage and fluid carryover fromone stream to the other.Heat exchangers may be classified according to transfer process, construction, flowarrangement, surface compactness, number of fluids and heat transfer mechanisms oraccording to process functions