Numerical study on the heat transfer characteristics of three-dimensional pulsating heat pipe.

Existing pulsating heat pipes (PHPs) have a closed loop on a two-dimensional (2D) plane, leading to a structural limit in heat transfer performance. This study solves the limitations of these existing PHPs by substituting a specific three-dimensional (3D) structure PHP. The numerical model (having a 2D structure PHP) was validated with the experiment, which shows the maximum error of 8.5 % in the results. Results show that additional flow occurred due to the 3D structure of the PHP, which enables improved heat transfer. Under uniform heating conditions, the thermal resistance and the temperature of the evaporator decreased by up to 14.7 % and 6.7 ·C, respectively. Finally, the heat transfer performance was compared for the entire 3D structure PHP under uniform and non-uniform heating conditions. The non-uniform heating conditions of the PHP increased the thermal resistance and temperature of the evaporator under low heating rates while decreased them under high heating rates. [ABSTRACT FROM AUTHOR]