Double Pipe Heat Exchanger
A Double Pipe Heat Exchanger is one of the simplest forms of Shell and Tubular Heat Exchanger. Here, just one pipe inside another larger pipe. To make a Unit very Compact, The Arrangement is made Multiple Times and Continues Serial and Parallel flow. One fluid flows through the surrounded by pipe and the other flows through the annulus between the two pipes. The wall of the inner pipe is the heat transfer surface. This is also called as a hairpin Heat Exchanger. These are might have only one inside pipe, or it may have multiple inside tubes, but it will forever have the doubling back feature shown. In some of the Special Cases the Fins also Used in Tube side
A primary advantage of a hairpin or double pipe heat exchanger is to facilitate it can be operated in a true counter flow pattern, which is the a large amount efficient flow pattern. That is, it will give the highest overall heat transfer coefficient for the double pipe heat exchanger design. Also, hairpin and double pipe heat exchangers can handle high pressures and temperatures well. When they are operating in true counter flow, they can operate among a temperature cross, that is, where the cold side outlet temperature is higher than the hot side outlet temperature.