HEAT PIPE SIMULATION UNDER CRITICAL CONDITIONS

Flow, heat and mass transfer in heat pipes has been studied extensively. This is due to the increasing need in understanding the complicated transport process for application of diverse fields. Recently one of the heat pipes which aroused the interest of research are the three dimensional heat pipes which incorporates the phase change mechanisms at the liquid and vapour interface. In this paper, an originally three-dimensional steady state model is developed coupling the hydrodynamic and thermal models in sintered heat pipe in cylindrical polar coordinate. The model predicts the heat pipes behaviors under critical conditions were a high heat input is exposed to its evaporator region. Such study has not been well investigated before and can be useful for academic, engineering and industrial purposes. Compared with its normal working conditions were heat pipes limits are not reached, the results illustrate well the function of the heat pipe and the circulation of the working fluid inside the heat pipe regions. Results show also that, for high heat input the circumferential velocity components increase specially in the liquid-vapor interface and the tangential velocity component has a significant effect on the phase change phenomena.