EXPLORING PASSIVE TECHNIQUES FOR THERMAL PERFORMANCE IMPROVEMENT

Heat transfer intensify techniques (passive, active or a combination of passive and active methods or compound methods) are commonly used in areas such as process industries, heating and cooling in evaporators, thermal power plants, air-conditioning equipment, refrigerators, radiators for space vehicles, automobiles, etc. Passive techniques, where inserts are used in the flow passage to intensify the heat transfer rate, are advantageous compared with active techniques, because the insert manufacturing process is simple and these techniques can be easily employed in an existing heat exchanger. In design of compact heat exchangers, passive techniques of heat transfer augmentation can play an important role if a proper passive insert configuration can be selected According to the heat exchanger working condition (both flow and heat transfer conditions). Many researchers have used different passive methods to improve heat transfer. Passive heat transfer methods are not only applicable in heat exchanger but also in solar air heater and cooling of electronic components (heat sink).