刷式密封流场和温度场数值模拟

Numerical Simulation on Flow and Temperature Distributions of Brush Seals

将刷式密封区域视为多孔介质,建立刷式密封CFD数值分析模型;结合FLUENT软件,通过求解Non-Darcian多孔介质模型的能量方程和(RANS)完全雷诺平均方程的方法,研究刷式密封干涉量、转速和压比对刷式密封流动和传热特性的影响规律;采用EUGRN方程推到出多孔介质阻尼系数计算方法,并通过试验验证该方法的正确性。结果表明:随着压比的增大,最高温度先增大然后减小;随着转轴与刷丝束间干涉量和转速的增加,最高温度增大;在每个转速下都存在一个临界压差可使得刷丝自由端最高温度达到最大值。

By regardin analysis model was g the brush seal region as porous media, the brush seal computer flow dynamics （CFD） numerical established.The effect of brush seal interference volume ,speed and compression ratio on the brush seal flow and heat transfer characteristics was studied by solving the energy equation of Non-Darcian porous medium model and （RANS） completely Reynolds-averaged equations method.A calculation method of porous medium damping coefficient was deduced based on EUGRN equation,and the correctness of this method was verified by experiments.The results show that with the increasing of compression ratio, the maximum temperature is firstly increased and then decreased.With the increasing of tow interference between the shaft and the brush and the speed, the maximum temperature is increased. At each speed,there is always a critical pressure difference so that the maximum temperature of the free end of the filament of brush reaches a maximum.