Novel air film hole with improved cooling efficiency

Abstract

The invention discloses a novel cooling hole capable of improving the cooling efficiency of an air film of a turbine engine. The novel cooling hole structurally comprises conical holes and a rectangular transverse groove. The rectangular transverse groove is formed in the conical holes along the direction perpendicular to the flowing direction of cold air. An included angle between the axis of each hole and a plane ranges from 10 degrees to 40 degrees, the conical holes are machined on the basis of cylindrical holes, an orifice of each conical hole is a conical opening with an opening angle which ranges from 10 degrees to 20 degrees, and the depth of the transverse groove ranges from 0.5D to 1.0D. Compared with conventional cylindrical air film hole structures, the novel cooling hole has the advantages that the exit sectional area is increased by the conical nozzle holes, so that the main flow penetrating ability of jet flow is reduced, reverse vortex pairs around the nozzle holes can be effectively suppressed, and accordingly the cooling efficiency can be improved; vertical fixed walls of the transverse groove at the lower edges of the conical holes can stop cooling air flow from flowing, so that parts of the cooling air flow flow to two sides of the novel cooling hole, and the novel cooling hole is favorable for transversely diffusing the cooling air flow; the cooling efficiency of the novel cooling hole can be improved by about 300% as compared with the traditional cylindrical air film hole under the condition of a certain blowing ratio.

Description

technical field [0001] The invention relates to the technical field of film cooling in turbine power devices, and is a new type of film hole capable of improving the cooling efficiency of gas turbine blades and combustion chamber walls, and is suitable for the cooling performance requirements of a new generation of high-performance aero-engines for high-temperature components. . Background technique [0002] With the rapid development of modern aero-engines, the temperature of the gas at the inlet of the turbine continues to increase, which increases the thermal load on the blades, resulting in a decrease in the performance of the blade materials and affecting the safe operation of the engine. According to the statistics of the authoritative department in the United States, more than 60% of the failures of aero-engines occur in high-temperature parts, and there is a rising trend. The life of some high-temperature parts of engines in my country is generally only a few hundred...

AI Technical Summary

Problems solved by technology

However, most of the current research focuses on opening transverse grooves at the outlet of cylindrical air film holes, and has not realized the effective combination of expansion holes and opening transverse grooves.

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