Experimental Investigation on the Temperature Distribution Characteristics of the Evaporation Section in a Pulsating Heat Pipe

With the increasing demand for heat dissipation in the electronics industry, pulsating heat pipe (PHP) has attracted wide attention due to its simple structure and excellent heat transfer ability. However, due to the unique operational mechanism of PHP, the temperature distribution in the evaporation section is obviously not even during the operational process of PHP. When the PHP is used as a heat dissipater, the evaporation section of the PHP directly contacts with the chips and has great influence on the performance of the chips, so it is very important to investigate the temperature distribution characteristics in the evaporation section. In this paper, both the effects of the filling ratio and heat flux on these characteristics were investigated. The experimental results indicated that the temperatures of the middle U turn were the highest. When the heat flux and the filling ratio were 364 W/cm(2) and 36.3%, respectively, the maximum temperature difference between the middle U turn and the other U turns could be as high as 18.92 K. Furthermore, the temperature differences between the middle U turn and the other U turns firstly increased and then decreased with the increase of heat flux and filling ratio.