Abstract
Heat exchanger is a widely used device used for transfer of heat energy of hot fluid to the cold fluid. The heat is transferred in form of conduction and convection. Conduction occurs inside the material whereas convection occurs from materials to fluid and from fluid to fluid. The common application of the heat exchangers are like condenser, cooling tower, intercooler, refrigeration, and many other industrial applications. There are many types of heat exchangers wherein parallel and counter flow heat exchangers are extensively used in parallel flow heat exchanger hot and cold fluids are passes through the tubes in the same direction where as in counter flow heat exchanger both the fluids are passes in opposite direction to produce the desired effect. Baffles are sometimes used in heat exchanger to enhance heat transfer efficiency of heat exchangers.