Numerical Analysis of Closed Loop Pulsating Heat Pipe Using CFD

Abstract

Closed loop pulsating heat pipe is very effective tool for removal of heat from very small electronic devices. Numerical model is developed is very helpful in observing the working phenomenon of CLPHP. A parametric study is carried out to find out the effect of various parameters like number of loops, position of CLPHP, Nature of Refrigerant used, filling ratio on the performance of CLPHP. It is been found that gravity plays a very important role in flow of liquid (refrigerant) in the pipe as cooling effect of vertical closed loop pipe is better than horizontal closed loop pipe. It is also observed that the pipe with 50% filling ratio has minimum thermal resistance with comparison with other filling ratios. As the heat input increases in the thermal resistance of the pipe decreases i.e thermal resistance of pipe is in inverse proportion with the heat input. It was observed that R134a performed better in comparison with all other refrigerants given the same operating conditions.