涡轮叶片尾缘开缝喷气的数值模拟和试验研究

以某涡轮叶栅为研究对象,采用试验和数值模拟相结合的方式研究了涡轮叶片尾缘不同喷气形式对叶栅性能的影响.应用一维源项喷气模型,结合涡轮叶栅流场数值模拟,得到了不同喷气形式下涡轮叶栅流场细节.计算与试验结果显示:两种开缝形式下,喷气比例对叶片表面参数以及出口气流角影响不大,但能量损失系数随着喷气比例的增大出现先增大后减小的趋势.对开缝时,喷气引入吹除了附着在叶片尾缘的漩涡,并增强了尾迹与主流的掺混过程;半开缝时,喷气的引入仅吹除了附着在开缝处的漩涡,对于尾缘处流场影响不大.

Experiment and Numerical Simulation Investigation of Turbine Blade with Trailing Edge Ejection

Numerical simulations and tests were carried out to investigate the effect of ejection from different trailing edge slots of a turbine cascade.The detailed flow field of ejection cascade was obtained by using a compact ejection model coupled with the calculation of main flow field.Numerical and experimental results show that the ejection ratio has little effect on the distribution of Mach number and exit flow angle of the two slot types.However,the energy degradation coefficient increases at first and then it has a decreasing tendency with the increase of ejection ratio.The ejection from the symmetric slot blows away the vortex at the blade trailing edge and strengthens the mixing of the wake with the main flow.The ejection from the half slot only blows away the vortex on the slot surface,and has little effect on the flow field near the trailing edge.