Effect of Dimensionless Number on Thermal Performance of Closed Loop Pulsating Heat Pipe: A Review

The objectives of this paper is to study effects of dimensionless numbers on thermal performance of the closed-loop pulsating heat pipe and to establish a correlation to predict the thermal performance of the closed loop pulsating heat pipe the heat pipes are made of long copper capillary tubes. Both ends were connected together to form a loop. Acetone, ethanol, methanol can be used as working fluids with constant filling ratio of 30 to 70 % by total volume. Thermal performance of closed loop pulsating heat pipe represented by Kutateladze number (Ku) and it depends on Prandtl number of liquid working fluid (Prl), Karman number (Ka), Bond number (Bo), Jacob number (Ja), and Aspect ratio (Le/Di). Moreover, thermal performance can be successfully established by analyzing all dimensionless numbers that have effect on the thermal performance of the closed loop pulsating heat pipe.