HEAT PIPES FOR ENHANCING THE PERFORMANCE OF THERMAL SYSTEMS: A REVIEW

In the recent years, Heat pipes are the most effective device of transporting heat from one point to another. In these devices the heat transport mechanism is based on the combination of conductive and convective heat transfer. Heat pipes basically have three different regions such as evaporator region, adiabatic region, and condenser region. This device does not require significant temperature gradient between heat sources and heat sinks instead the temperatures available should be sufficient enough to boil the working fluid present inside it. The effectiveness of heat pipes is due to the latent heat of phase change of the working fluid within condensation and evaporation regions. The main components of heat pipe include- heat transfer fluid, wick and the container. The working fluid absorbs heat in the evaporator region and turns to vapour state. This vapour moves from the evaporator region to the length of the pipe and condenses in the condenser region, which has a lower temperature, hence converting it back to liquid. This liquid then returns back to evaporator through capillary action. This review attempts to cover various types of heat pipes, container material, types of wick material, and various heat transfer fluids for different thermal energy applications.