Study on the startup and heat transfer performance of loop heat pipe under sloshing conditions

In order to investigate the startup and heat transfer performance of a loop heat pipe under oscillatory conditions, a self-designed experimental setup for a disk-shaped evaporator loop heat pipe was used. This study focused on the startup performance, operational characteristics, and heat transfer properties of the loop heat pipe at different sloshing angles (0 degrees, 5 degrees, 10 degrees, and 15 degrees) under various heating loads and fill ratios. The results revealed that under oscillatory conditions, as the sloshing angle increases, the steady-state operating temperature curve of the evaporator exhibits a consistent trend. Increasing the heating load results in the loop heat pipe reaching quasi-steady-state more rapidly. However, with an increase in the sloshing angle, the startup time of the loop heat pipe also lengthens. The loop heat resistance gradually decreases with an increase in heating load, eventually stabilizing. Notably, when sloshing angles are present within the same power range, the loop heat resistance for 50% and 70% fill ratios exhibits a trend of initially increasing and then decreasing, while for a 60% fill ratio, the loop heat resistance increases with the sloshing angle.