Structure for improving aerodynamic efficiency of low-pressure turbine blade and working method of turbine blade

Abstract

The invention provides a structure for improving aerodynamic efficiency of a low-pressure turbine blade. The structure comprises a suction surface, a pressure surface, recesses and a blade body, wherein the suction surface is an outer convex surface of the blade body, and the pressure surface is an inner concave surface of the blade body; the recesses are arranged on the suction surface in pairs, and an inclination angle beta is formed between each recess and airflow; and when airflow flows through the surface of the blade body, one ends of the recesses adsorb low-energy fluid, the low-energy fluid spirally flows in the recesses in the inclined direction to form a spiral vortex, and the spiral vortex is discharged from the other ends of the recesses, wherein the airflow comprises the low-energy fluid and high-energy fluid. According to the structure for improving the aerodynamic efficiency of the low-pressure turbine blade, the spiral moving vortex is generated inside the inclined recesses on the surface of the turbine blade, and high-strength and large-range flow attachment is generated on downstream sections of the recesses, so that flow separation on the wall face of the rear part of the blade body is delayed, and the structure obtains a better turbine blade drag reduction effect.

Description

technical field [0001] The invention relates to the technical field of aeroengine power blades, in particular to a structure for improving the aerodynamic efficiency of a low-pressure turbine blade and a working method thereof. Background technique [0002] Gas turbines are important components in aero engines. When the aeroengine is running, the gas turbine uses high-temperature and high-pressure gas as the working medium, and uses the expansion of the working medium to generate mechanical work. Its function is to convert the thermal energy of the gas into mechanical work. [0003] After the high-temperature and high-pressure gas flows through the passage between the turbine blades, the temperature and pressure of the gas flow are reduced, realizing the conversion of the internal energy of the gas to kinetic energy and then to mechanical energy; the gas flow process interacts with the force generated by the turbine blades, and the turbine makes a mechanical achievement. I...

AI Technical Summary

Problems solved by technology

But the weak point of this prior art is that for the turbine blade that is arranged with this depression, can only be applicable to the working condition that main stream flow separation occurs in the depression position; change (in advance, or delay), the flow control drag reduction effect of this expansion-shaped sag will be limited, and even play the opposite drag increase effect under the mainstream condition of high Reynolds number

This makes the backside-suction side of the turbine blade prone to flow separation, especially under low Reynolds number flow conditions. In the range of Reynolds number 5000-50000, the kinetic energy of the fluid in the boundary layer is low, and the curved high-load turbine blade wall is more likely to cause flow Separation brings large turbine aerodynamic loss, reduces the flow capacity of the turbine, reduces the energy conversion efficiency of the turbine, and increases the fuel consumption of the engine

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