Numerical Simulation And Characteristics Analysis Of The Liquid Film Based On Oscillating Heat Pipe

Numerical simulation and analysis on characteristic of the liquid film are carried on to represent the process mechanism of starting and operating of oscillating heat pipe by exploiting ANSYS FLUENT software in this paper. The oscillating heat pipe has simple structure, but its work principle and flow characteristics are very complicated. If affect factors are set inappropriately, for example diameter of the pipe, liquid-filled rate, type of working fluid, quantity of heating, angle of arrangement and so on, the process of starting and operating can not carry out normally. In order to define the pipe size and working conditions during simulation, geometry and physical factors which have an important impact on oscillating heat pipe are analyzed firstly. Due to the possible influence of scale effect of oscillating heat pipe on simulation results, microscale effect of oscillating heat pipe and its liquid film are both analyzed and some detail problem should be noticed combining liquid film theory of the pipe during simulation secondly, such as, surface tension, wall adhesion, contact angle and so on. The process of oscillating heat pipe is problem of closed flow field, no initial potential difference, unsteady, phase transition, heat and mass transfer. For obstacles may be encountered and the situation of narrow and complex flow field which lead to quantity and difficulty of simulation increase, so operational problems of mesh type, solution controls, precision format and flow model are analyzed and some definition of physical values and parameters prepared fully for the simulation of this paper. Simulation results are obtained by a lot of model form which the formation and development of liquid film as bubbles birth, the morphological change of interface liquid film of gas and liquid plug with the case of wall adhesion, the function of heat and mass transfer of liquid film with starting process and status change of flow which is caused by liquid film fluctuation and operation of oscillating heat pipe are analyzed.