Experimental study on the performance of a dual diameter closed loop pulsating heat pipe vertical and horizontal position

Abstract

This study comprehensively evaluates dual diameter Closed Loop Pulsating Heat Pipes (CLPHPs) with ethanol, methanol, and ethylene glycol at 50% and 60% filling ratios, focusing on their thermal performance at 0- and 90-degrees orientation. Addressing a significant gap in empirical data, our findings substantiate the theoretical advantages of dual-diameter designs, particularly in horizontal orientations. The 0-degree angle and a 60% ethanol filling ratio emerged as the optimal configuration, achieving the lowest thermal resistance, and demonstrating the potential for enhanced heat transfer efficiency in CLPHPs. These results suggest that the dual-diameter approach, tailored with appropriate working fluids and filling ratios, can significantly improve thermal management systems, with implications for electronics cooling and aerospace applications. Future research should further optimize these parameters to harness CLPHPs' capabilities fully across diverse operating conditions.