Turbine vane endwall cascade passage type assembly gap structure based on transverse pressure gradient

Abstract

The application discloses a turbine guide vane end wall cascade channel type assembly gap structure based on a transverse pressure gradient and belongs to the field of gas turbine turbine end wall cooling. The assembly gap is a cascade channel type structure with consistent axial cross section configurations, the pressure side wall surface is similar to the blade pressure surface profile, the suction side wall surface is similar to the blade suction surface profile, and the pressure side wall surface and the suction side wall surface jointly form a flow channel capable of generating a stable transverse pressure gradient; a leakage hole is formed in the seal piece. The seal cooling gas entering the gap from the leakage hole is actively regulated by the transverse pressure gradient, so that the seal cooling gas orderly migrates from the pressure side to the suction side and flows close to the wall surface, and the adiabatic temperature distribution in the gap and the gas film coverage of the suction side wall surface are significantly improved. Meanwhile, the leakage flow and the end wall gas film hole cooling gas synergistically act, the cooling effect and uniformity of the downstream surface of the end wall are enhanced, the net heat flux reduction amount is significantly improved, the mixing loss is reduced to a certain extent, and a good balance between efficient and uniform cooling and low aerodynamic loss is achieved.

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