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

Abstract

This research compares the thermal performance of two working fluids, Methanol, and distilled water, in a closed-loop pulsating heat pipe. The investigation explores the impact of these fluids on the thermal resistance of the system at different heat inputs and configurations. At an initial heat input of 10 watts, Methanol exhibits a higher thermal resistance of 4.8 than distilled water, which records a thermal resistance of 5. However, when considering the overall performance, Methanol outperforms distilled water. The optimal configuration for Methanol is achieved with a 60% filling ratio and a 90-degree inclination angle, resulting in a thermal resistance of 4. Distilled water initially exhibits higher thermal resistance at the 10-watt heat input, but it shows promise when used with a 60% filling ratio and a 90-degree inclination angle, with a thermal resistance of 1.4. However, as the heat input exceeds 40 watts, distilled water with a 60% filling ratio and a 90-degree inclination position outperforms other configurations. Based on the analysis, Methanol is the optimal working fluid in the closed-loop pulsating heat pipe experiment. Although initially demonstrating higher thermal resistance, it achieves the best overall performance with a 60% filling ratio and a 90-degree inclination angle. Distilled water performs less favorably in terms of thermal performance throughout the experiment. It is important to note that the specific results presented in this research depend on the provided information. The closed-loop pulsating heat pipe's design, size, and experimental conditions can influence its thermal behavior