1993 年 13 巻 Supplement2 号 p. 143-146
In the large-scale gas or steam turbine, the flow around the blade tip becomes transonic, and the shock waves are generated in the blade passage. These shock waves induce the boundary layer separation and the vibrations of blades. This unstable flow phenomenon is closely related to the secondary flow associated with the large change in flow direction in the blade passage. To simulate the flow in the blade passage, the rectangular duct with swept-back bump was made. The laser-induced fluorescence (LIF) method previously developed was applied to measure the temperature distribution in the duct, and the complicated pattern of the three-dimensional transonic flow field was clarified.