亚 声 速 压 气 机 平 面 叶 栅 风 洞 标 准 模 型 建 立

The standard model for linear cascade wind tunnel is the key to the construction of axial compressor design system and the standardization of linear cascade testing technique. The standard model of compressor cascade with a typical controlled diffusion airfoil is designed and tested based on the linear cascade wind tunnel of Northwestern Polytechnical University. The flow quality of the standard cascade including inflow precision，flow periodicity，and two-dimensionality is adjusted by a self-established integrated control system. On the basis of ensuring the flow quality，the performance of the standard cascade is measured，including the features of incidence and axial velocity density ratio，as well as the distributions of surface isentropic Mach number and wake，and is then compared to the reference cascade data published by DLR. The results show that the standard cascade exhibits good flow periodicity and accuracy，including a uniform region over four successive blade passages upstream and a periodicity range over two successive blade passages downstream，and the periodicity index of outflow is less than 2. The deviation of the inlet Mach number and axial velocity density ratio in the measuring blade passage is no more than 0. 005 and 0. 02，re-spectively. The comparison with the reference cascade data shows that the variation laws of the loss，exit flow angle and static pressure ratio with the inlet flow angle are essentially the same between the standard cascade and reference cascade at the design inlet Mach number of 0. 62. The loss and exit flow angle of the standard cascade are larger than those of the reference cascade due to the difference of measuring position downstream of cascade，but the static pressure ratio is basically the same. The distributions of the surface isentropic Mach numbers for the two sets of cascades are highly consistent. In general，the test data for the established standard cascade are comprehensive and reliable.