Transient Process Analysis of Oscillating Motion in Oscillating Heat Pipes

During the startup phase, oscillating heat pipes (OHPs) exhibit a transient process in which the working fluid moves erratically until a steady-state oscillatory flow is attained. Understanding the transient process is important to predict how long it takes an oscillating heat pipe to reach normal operation and realize its heat transfer potential after it is started. In this paper, we perform a theoretical study of the transient process of oscillating heat pipes. Based on a one-dimensional mathematical model, we obtain an analytic solution that allows us to predict transient process characteristics of oscillating motions in an oscillating heat pipe, as well as the impact that different design and operating parameters have on this transient process.