A mass-spring-damper model of a pulsating heat pipe with asymmetric filling

A pulsating heat pipe (PHP) is a device that transfers heat from a hot spot to a cold side by oscillating liquid slugs and vapor plugs. Its working principle is based on interplay between convective heat transfer, evaporation of the liquid at the hot side and condensation of the vapor at the cold side. Several factors play an important role including pressure differences, frictional forces, inertia forces, capillary forces and gravitational forces. In this paper, a 1D mass-spring-damper model is developed to predict the motion in PHP. Also, a heat transfer model is developed. These two models are coupled to analyze the motion and performance of a PHP and can also take asymmetry into account. Simulations show that, if there is mirror symmetry in the PHP, no net motion will occur resulting in a poor heat transfer performance. Thermal performance results are compared with experimental results from literature and show good agreement