Heat Exchangers
General Information About the Types of Heat Exchangers During the decision of selecting type of a heat exchanger, construction material, pressure and heat, performance parameters (temperature setup, flow, pressure gradient), tendency of contamination, consultation, cleaning, insertion and maintenance, type of fluids and their phases, the size of the heat exchanger, availability and the economic conditions should be considered. The basic rule to select the proper type of a heat exchanger is, based on experience, to choose a kind that carries out similar functions and works under the same conditions, and therefore the experience of company, which decides on the type of a heat exchanger is very important. After an elaborate search with experience, if found to be any of heat exchangers that work under the same conditions, a decision is made on the use of a proper heat exchanger.
Shell-and-Tube and U-Tube Heat Exchangers Shell-and-tube heat exchangers, with the estimated 60% of use and convenience for higher-pressure applications, are the most commonly used heat exchangers in the process industries (i.e. oil refineries, large chemical processes). Shell-and-tube heat exchanger, whose tube axis is constructed parallel to its shell axis, is made of cylindrical tubes that are parallel to each other. These cylindrical tubes are installed in a big cylindrical shell. One fluid flows inside the tubes, and another fluid flows over the tubes through the shell in a parallel or a diagonal way.
Qualifications:
-Maximum efficiency: e=0,9 (the efficiency is lower in numerous transitive units)
Advantages:
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