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对前缘上游端壁有单排和双排孔冷却的大尺寸低速涡轮导向叶栅进行了气动测量、热示踪和端壁流场显示 ,在吹风比 1～ 3范围获得了叶栅内的详细流场、冷气的空间分布和端壁上的流动图案。结合先前测得的没有冷却时的流场数据 ,这些结果表明端壁气膜冷却对叶栅流场结构有重大影响 ,吹风比是主宰射流与二次流间相互作用的主要因素 ,双排孔喷射使冷气比单排孔喷射更贴近端壁。低吹风比喷射冷气不能到达压力面并被二次流逐渐卷离端壁 ;中吹风比喷射有效的抑制了二次流的形成 ,并使端壁流线偏向于无粘流流线 ,冷气很均匀的覆盖在端壁上 ;高吹风比喷射可将冷气抛射到压力面上 ,双排孔情况下甚至使二次流反向 ,并形成一个与传统通道涡旋向相反的通道涡
The aerodynamic measurement, thermal tracing and endwall flow field show that the large-size low-speed turbine guide cascade with single-row and double-row holes cooling on the upstream edge of the leading edge has the function of Detailed flow field, spatial distribution of cooling air and flow pattern on the end wall. Combined with the previously measured data of the flow field without cooling, these results show that the film cooling on the end wall has a significant effect on the cascade flow field structure. The blow ratio is the main factor that dominates the interaction between the jet and the secondary flow. Jetting brings the cooling air closer to the end wall than single-row holes. The low air-to-air ratio can not reach the pressure surface and is gradually separated from the end wall by the secondary air flow. The medium air-blow ratio effectively suppresses the formation of the secondary air flow and biases the end-wall flow line to the non-stick flow line. Uniform coverage of the end wall; high blowing than the jet can be injected into the cold air pressure on the surface, even double-row double reverse flow direction and form a vortex channel with the opposite vortex of the traditional channel