可调高压导叶对1+1/2对转涡轮性能影响的数值研究

Effects of high-pressure guide vane adjustment on 1+1/2 counter-rotating turbine

对1+1/2对转涡轮高压导叶转动不同角度后不同落压比时的涡轮性能进行了数值计算和分析,获得了不同导叶开度和不同落压比对涡轮性能影响的关系曲线.结果表明,高压导叶转角的变化可以有效地调节1+1/2对转涡轮的流量;当导叶打开时,随着落压比的变化涡轮效率存在一个峰值,当导叶关闭时,涡轮效率随落压比的减小持续降低,并且降低的幅度更加明显;当涡轮压比较低时,导叶开大时的涡轮效率略高于导叶未动时的效率,并且随着落压比的进一步降低,差异更加明显,这与文献中常规涡轮导叶调整后涡轮效率均会降低明显不同;在保证效率和功量的前提下,高压导叶开大对于1+1/2对转涡轮高低压级出功比保持在合理范围内是有利的.

A detailed numerical simulation was carried out to investigate the 1＋1/2 counter-rotating turbine performance with different openings of high-pressure guide vane and turbine expansion ratios.By analyzing the results,the variable high-pressure vane could effectively control the massflow of 1＋1/2 counter-rotating turbine;when the high-pressure guide vane was opened,there was a peak turbine efficiency with the change of the expansion ratio,when the high-pressure guide vane was closed,the efficiency decreased steadily with the reduced expansion ratio,and the efficiency reduced more quickly than that when the high-pressure guide vane was opened;in the case of the lower expansion ratio,the efficiency improved with the increase of the opening of the high-pressure guide vane,and the improvement was more obvious with the decrease of expansion ratio,which is significantly different from the efficiency of conventional turbine that generally decreases in the variable guide vane;the results show that the opened high-pressure guide vane is favorable for the specific work ratio（SWR） of high-pressure turbine to that of low-pressure turbine remained within reasonable limits.