Heat exchangers are devices used to transfer heat between two or more fluid streams at different temperatures. Heat exchangers find widespread use in power generation, chemical processing, electronics cooling, air-conditioning, refrigeration, and automo- tive applications.The simple type of heat exchanger is double pipe heat exchanger. In this experiment, the working princples a concentric tube heateexchanger operating under parallel and counter flow conditions was observed and the effect of hot water flow rare and hot water temperature variation the performance characteritics of a concentric heat exchanger were observed.

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