1+1/2对转涡轮全环非定常数值模拟

Numerical simulation of full scale unsteady flow in 1+1/2 counter-rotating turbine

采用三维数值模拟方法对1+1/2对转涡轮进行了全环非定常计算,对比了定常结果与非定常时均结果的总体参数。在非定常流动中,分析了激波、尾迹、位势作用及泄漏流等因素对叶片表面负荷分布和局部区域流场的影响。结果表明:非定常效应对高压导叶流场影响很小;在激波、尾迹、位势作用等的共同影响下,高压动叶内流动呈现出较强的非定常性,二次流动增强;低压动叶方面,虽然与上游叶排轴向间距较大,但其流动非定常性依然显著,且受影响范围更广。

Study on full scale unsteady flow in 1＋1/2 counter-rotating turbine was presented by three di-mensional numerical simulations. The total results were compared between steady and unsteady time-aver-age simulations. In the unsteady flow, the impact of the shock wave, wake, potential interaction and leakageflow and other factors on the blade surface load distribution, local area flow field were analyzed. It is re-marked that unsteady interaction has little effect on the flow in high-pressure guide vane; under the com-bined effect of the shock wave, wake, and potential interaction, there is a strong unsteady effect on flow fieldof high pressure rotor and secondary flow in it is enhanced; in aspect of low pressure rotor, the unsteady ef-fect is more significant in a wider range, although the axial gap is larger between high pressure rotor and lowpressure rotor.