双级风扇三维粘性非定常流动的数值解

针对一台双级跨音速轴流风扇动静叶片排相互干扰的三维非定常流动,进行了N-S方程的数值求解。首先计算风扇定常流场,以定常流收敛结果为起始场计算非定常流动。计算结果表明,非定常流动对各叶片排进口气流角有较大的影响,其中静叶的变化大于动叶,与定常流结果相比,非定常的瞬态攻角增大的量大于减少的量,最多时增大近10°左右。静子叶片受到的非定常气动力变化幅度也大于转子叶片,叶片排所处的轴向位置不同,非定常流动的影响会有较大的差别。

Numerical Solutions of 3D Unsteady Viscous Flow in a Two-Stage Fan

The numerical simulations of the unsteady flow induced by rotor-stator interaction in a two-stage fan were carried out.A three-dimensional unsteady Navier-Stokes equations solver using a high-resolution finite difference has been developed.It can be used for the calculation of steady flow field with an implicit scheme.The solution of steady flow was firstly obtained by this code.The unsteady flow computations were started from this solution.The unsteady flow results show that the unsteady effects on inlet flow angles of blade rows are significant.The variations in inlet flow angles of stator blades are larger than that of rotor blades.In comparison with the steady flow solution,the increases in unsteady flow attack angle are larger than the decreases.The maximum increase is about 10 degrees.The variations in unsteady aerodynamic force on stator blades are also larger than that on rotor blades.The unsteady flow effects caused by several blade rows are different from that by single blade row.