Numerical Simulation on Flow and Heat Transfer in Oscillating Heat Pipes

Abstract

In order to predict the heat transport capability of oscillating heat pipes (OHPs), a mathematical and physical model of OHP was built to simulate the process of flow and heat transfer in vertical bottom heating mode. Water was used as working fluid. Mixture model in FLUENT was used for twophase flow numerical simulation. The result showed that the numerical simulation was successful to reproduce the behavior of the internal flow of OHP, including vapor generation in evaporation section, oscillation phenomena caused by the pressure difference and heat transfer due to oscillation. Comparing with the experimental tests, the simulation results agreed with the experimental records fairly well.

Gas Loss Mechanism in the High-Pressure Air Cushion Surge Chamber of Hydropower Station for Transient Process

“…Based on the VOF model, Zhu Hairong [23,24] introduced the Level Set function to establish a coupled model, which can effectively simulate the transient distribution and dynamic changes of two-phase flow and significantly improve the accuracy of heat transfer calculations. Based on the two-phase flow model, Zhang Yumin [25] added a corresponding module into Fluent as the source term of evaporation and condensation in the mass transfer heat transfer equation, and accurately simulated the heat transfer phenomenon in the gas-liquid phase variation process in the thermosiphon.…”