Experimental Investigation of Parameters Affecting Performance of Pulsating Heat Pipe

Pulsating heat pipe (PHP) is a two phase highly efficient heat transfer device, due to its simple and flexible construction; it can be manufactured for a variety of applications. PHP works on thermally induced self-sustaining oscillation of liquid plugs and vapor slugs, so it does not have any moving parts either. Ease of manufacturing, potential for high efficiency at different scales and the ability to handle large heat fluxes has the PHP a suitable candidate for microscale electronics cooling or power electronics cooling. However, this technology is still in developing phase and there is at present no comprehensive model which can be used to design a PHP for a specific application. There are many parameters which affect PHP operation and a thorough understanding of the relation between all the variables is first required. The present study is an attempt to investigate experimentally the effects of various parameters on PHP startup, based on startup temperature measurements under varying heat input and carefully controlled conditions. It has been observed that the oscillations in PHP start (startup) as soon as it reaches a minimum temperature corresponding to the minimum Etvos number required for vapor bubble rise.