Numerical Simulation Of Interface Shape Change Of Two Phase Flow In Oscillating Heat Pipe

As a new type of high efficient heat transfer component, Oscillating Heat Pipe has a simple structure and good heat transfer performance, low cost, strong adaptability, etc. And attract the attention of scholars from all over the world. It has been widely applied in electronics cooling, air conditioning, waste heat recovery, and other fields. And it has a great development potential. When Oscillating heat pipe work, accompanied by phase transformation and complex pipe pressure and temperature changes, especially in the evaporation and condensation, Intense heat transfer led the tube show complex two phase flow, the formation and the transformation of flow pattern have a great affects on the performance of oscillating heat pipe, The two-phase flow model is decided by the heat flux, the surface parameters, the fluid property and other aspects reasons, So the study of the interface morphology change of the two phase flow in pipe has a great significance.According to two phase flow interface morphology change in oscillating heat pipe, use VOF two-phase flow model, and add the CSF surface tension model, use ANSYS FLUENT14.0 solver to do the computing research. At first, the formation mechanism of plunger flow in capillary T pipe was studied, obtained the Relationship between the plunger length and the branch pipe radius, and get the best simulation environment of two phase flow. Then the model of bubble motion and deformation inside the capillary has been established, through by contrast with the results of experiment and LBM method by other scholars, prove that the model has good accuracy. The deformation law and oscillation rule of bubble in capillary pipe has been studied in different cases of Re number, We number, Ca number. The critical capillary value of bubbles burst in capillary pipe will increase with the increase of bubble diameter. Flow pulsation and interface wave cause by pressure pulsation will increase the degree of the flow disorder.The motion and deformation of Two parallel free-falling droplets in the gravitational field has been simulated base on FTM(Front-Tracking Method) by MATLAB software. The situations of different parameters, which are Reynolds number, Eo number and droplet initial center distance, have been studied by this method. The results show that: when the two droplets is closely(L/D=2), the deformation of droplet is asymmetric, and the droplet will repel each other; when Eo number is large, the deformation of droplet is pronounced, and the droplet repels each other more, the velocity of vertical position is smaller; when the distance is large, the impact is little, and the characteristics of the droplet’s movement is determined by the Re number and Eo number; when Re number is large, the deformation is more frequent.