Effect of Working Fluid, Heat Input and Filling Ratio’s On Performance of Closed Loop Pulsating Heat Pipe

Abstract

Semiconductors are the main source for rapid response of electronics components. Thermal loads are responsible for serious damage of electronic components, which causes data loss. In order to improve the thermal management of electronic components, study on novel cooling systems for modern electronics is taking dominant importance. A new closed loop pulsating heat pipe (CLPHP) system has been proposed in this study.An experimental investigation on various filling ratio, heat input and time duration using CLPHP system for two working fluids (Ethanol and Acetone) was conducted using a copper tube of 2.8 mm diameter and 210 mm length with 3 bents. The experimental results showed compared to acetone, ethanol has given the minimum start up power and minimum thermal resistance for 50% filling ratio. The pulsation of Ethanol started dominating above 70 W of heat input for all the filling ratios. The temperature and thermal resistance were found lesser and a noticeable increment in heat transfer coefficient for filling ratio of 50% at the same heat input. For acetone, it is found that 50W is the optimal heat input for pulsations to start and sustain in all the filling ratios, but gave the better result in terms of lower temperature, thermal resistance and higher heat transfer coefficient for filling ratio of 60%.