Experimental study on the thermal performance of a closed loop pulsating heat pipe with various position.

Abstract

Research on closed loop pulsating heat pipes (CLPHPs) using Methanol and Ethylene Glycol as working fluids elucidates key design considerations for maximizing thermal performance. Both studies concur that a 50% filling ratio optimally balances vapor and liquid phases to facilitate effective pulsating flows. However, optimal inclination angles varied; Methanol achieved peak performance at 45°, while Ethylene Glycol was most effective at 35°. Regardless of the working fluid, vertical orientations at 90° yielded the poorest performance due to flow stratification effects. The findings indicate that an angled orientation between 35-45° significantly improves thermal efficiency, though the exact optimal angle may be fluid-specific and warrants further investigation