Experimental study of a closed loop pulsating heat pipe aiming at assessing the optimized operational conditions

In recent times pulsating heat pipes turn into a pleasing field of study for researchers as useful devices to enhance and intensify heat transfer. Experimental data under various operating conditions for a better theoretical understanding are needed. This paper presents an experimental study on a closed loop pulsating heat pipe made of copper with 14 U-turns. The experiments were carried out for different working fluids (acetone, distilled water, ethanol and methanol) and their mixing, heat input, filling ratio and evacuation levels to optimize operational conditions. Thermal resistance at steady state specified for performance evaluation and showed better results for acetone. The mentioned working fluids in filling ratio of 60 % have better operation and acetone has the best. As well as experiments in different evacuation levels showed, more evacuation lead to more performance.