Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Experimental Study on the Effects of Upstream Wakes on Cascade Flow

상류 후류의 익렬 유동에 미치는 영향에 대한 실험적 연구

  • Published : 2001.03.01
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Abstract

This paper is concerned with the effect of cylinder wakes upstream on blade characteristics of compressor cascade(NCA 65 series). At first, it is found that the velocity defect ratio of cylinder wake varies according to the acceleration and deceleration in a flow field but, is conserved nearly constant at flow downstream the cascade, irrespective of the flow path in the cascade. When a cylinder wake flows along near the suction surface of the blade, or impinges on the leading edge, the turbulent velocities are supplied on or inside the outer edge of boundary layer near the leading edge of suction surface, and the transition to a transitional or turbulent boundary layers is induced, so that the laminar separation is prevented, but the profile loss increases. The transition of boundary layer to a transitional or turbulent one is strongly related with the strength of added turbulent velocities near the leading edge on the suction surface, which is influenced by the flow path of a cylinder wake.

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References

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