电弧增材熔池流动特性和稳定性数值模拟OA北大核心CSTPCD

In order to explore the influence of the thermal state and flow characteristics of the molten pool on the size and stability of the molten pool,a three-dimensional numerical model of the arc additive molten pool was established by using FLUENT software and secondary development.The numerical results show that the arc additive is a non-equilibrium solidification process with rapid heating and rapid cooling in the molten pool.The arc force and Marangoni effect have great influence on the flow in the molten pool,and the flow pattern in the molten pool is dominated by circulation.The effects of heat input and heat dissipation on the local temperature field and flow field in the molten pool are comprehensively analyzed.The hot state of molten pool changes the flow state and velocity of molten pool by affecting the melt viscosity and driving forces.The flow of molten pool affects the boundary of molten pool and thermal convection.Therefore,the combined effect of the two determines the molten pool geometry.The interlayer cooling can improve the heat dissipation condition of molten pool during deposition and reduce the effect of heat accumulation,but it will reduce the forming efficiency.