超声速槽道流动中的湍动能负产生率研究

Study on Negative Production of Turbulent Kinetic Energy in Supersonic Channel Flow

局部湍流的逆向传递会导致湍动能输运方程中的湍动能产生率项符号的改变,由一般正值变为负值。研究湍动能负产生率的变化可以实现调节通道内的气流品质,有利于进行流动控制。对二维超声速槽道流动进行数值模拟,研究超声速流场中湍动能负产生率的变化规律。结果表明:湍动能负产生率是由流场应变率张量的拉伸特性主导;激波处湍动能产生率恒正且取得极大值;增大入口马赫数会使湍动能负产生率效应减弱。

The reverse transfer of local turbulence causes the change of the sign of the turbulent kinetic energy production in the transport equation from positive to negative.Reserch on the change of negative production of turbulent kinetic energy can adjust the quality of airflow in the channel and is beneficial to flow control.Numerical simulation of the two-dimensional supersonic channel flow is carried out to analyze the changing law of NPTKE in the supersonic flow field.The results show that NPTKE is dominated by the tensile properties of the flow field strain rate tensor,the lturbulent kinetic energy production rate at the shock wave is constant and positive,and reaches a maximum value.The increase of inlet Mach number will weaken the effect of NPTKE.