封闭容器内短路燃弧压力升计算仿真参数分析

Simulation parameter analysis of short circuit arc's pressure rise calculation in closed container

建立了开关柜封闭容器物理模型,并基于CFD的间接耦合分析方法,采用CFX仿真分析了小封闭容器内短路燃弧压力升分布,并分析了网格数量、仿真时间步长、电弧尺寸以及电弧位置等参数对计算结果的影响。分析表明:当网格数达到一定程度时,增大网格数量对计算结果影响不大,同时电弧尺寸和电弧位置对封闭容器短路燃弧压力升影响较小;仿真时间步长对计算结果存在一定的影响,综合计算效率和计算精度建议前3 ms采用自适应时间步长,3 ms后采用固定步长分析。

A physical model of closed container for switch gear was established.Meanwhile,the distribution of the short circuit arcing pressure in the small enclosed container was simulated by ANSYS CFX based on the CFD indirect coupling analysis method.In addition,the influence of parameters such as grid quantity,simulation time step,arc size and arc position on the calculation of short-circuit arcing pressure in closed container were analyzed. Research showed that when the grid number reached a certain level,the number of grid increases has little effect on the calculation results.Besides,the arc size and arc position have little effect on the simulation result.The simulation time step has some influence on the calculation result,and its selection should consider the calculation efficiency and calculation precision.it was recommended that adaptive time step should be adapted in the first 3 ms and fixed step size analysis should be adapted after 3 ms.