端壁组合射流对高速扩压叶栅损失特性的影响

发布时间：2018-01-21 00:17

本文关键词： 扩压叶栅流动损失端区流动组合射流　出处：《推进技术》2016年09期 　论文类型：期刊论文

【摘要】：提出了一种端壁组合射流技术以控制进口马赫数0.67的高速扩压叶栅端区流动。通过前缘射流旋涡可以增强端壁附面层与主流间的流体交换,阻碍横向二次流动,减小角区低能流体堆积;而采用角区射流注入能量能够进一步减弱吸力面侧流动分离。以上组合控制方法可较单独采用前缘或角区射流更有效减小栅内损失,提高其气动性能。当角区射流位于近吸力面侧的分离起始位置附近时,其改善栅内流动的效果最佳;远离吸力面的端壁射流则可抑制端区低能流体横向迁移及其与分离区流体间的相互作用,但其减小损失的效果弱于近吸力面侧的射流。随着射流总压比的增加,组合射流减小损失的效果先增加后减小;过大的总压比会加剧射流与来流间的掺混损失,使得叶栅气动性能恶化。当射流总压比为1.2时,损失减小最大可达12.6%,而射流流量仅相当于叶栅进口流量的0.64%。
[Abstract]:A combined end-wall jet technique is proposed to control the flow at the end of a high-speed diffuser cascade with an inlet Mach number of 0.67. The flow exchange between the end-wall boundary layer and the mainstream can be enhanced by the leading edge jet vortex. It hinders the lateral secondary flow and reduces the accumulation of low-energy fluids in the corner region. The angular jet injection energy can further weaken the suction side flow separation. The combined control method can reduce the loss in the grid more effectively than the front or corner jet alone. Improve its aerodynamic performance. When the angular jet is near the starting position of separation near the suction surface, the effect of improving the flow in the grid is the best. The end-wall jet far from the suction surface can inhibit the lateral migration of the low-energy fluid in the end region and its interaction with the fluid in the separation zone, but the effect of reducing the loss is weaker than that of the jet near the suction surface. The total pressure ratio of the jet increases with the increase of the total pressure ratio of the jet. The effect of combined jet to reduce the loss increases first and then decreases; When the total pressure ratio is 1. 2, the loss of mixing between the jet and the flow will be increased, and the aerodynamic performance of the cascade will deteriorate. When the total pressure ratio of the jet is 1. 2, the maximum loss can be reduced to 12.6%. The jet flow rate is only 0.64% of the inlet flow rate of the cascade.
【作者单位】：哈尔滨工业大学能源科学与工程学院;
【基金】：国家自然科学基金(51306042)
【分类号】：V231
【正文快照】： 1引言端区流动是影响压气机效率及其工作可靠性的最重要因素之一,尤其是在现代高负荷低展弦比压气机中,端区损失甚至可达总损失的50%以上[1]。因此,如何减弱端壁附面层横向迁移及其与吸力面侧附面层相互作用而导致的流动分离,已成为叶轮机械气体动力学领域最重要的研究内容之

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