A piece of equipment built for efficient heat transfer from one medium to another.
A heat exchanger is a piece of equipment built for efficient heat transfer from one medium to another. They are widely used in space heating, refrigeration, air conditioning, power plants, chemical plants, ood and manufacturing industries, petrochemical plants, waste heat recovery, petroleum refineries, natural gas processing and sewage treatment.
Heat Exchangers may be classified according to the following criteria. •Transfer process: direct and indirect contact •Geometry of construction; tubes, plates, and extended surfaces. •Heat transfer mechanism: single phase and two phase •Flow arrangement: Parallel, counter, cross flow.
According to transfer process heat exchangers are classified as direct contact type and indirect contact type. In direct contact type, heat is transferred between cold and hot fluids through direct contact of the fluids (eg. Cooling towers, spray and tray condensers) In indirect heat exchanger, heat energy is transferred through a heat transfer surface.