A double wall heat shield for an afterburner

Abstract

The invention discloses a double-layer-wall heat insulation screen used for an afterburner. Cooling protection is formed for the wall surface of the afterburner by using an inner convection cooling mode and a gas side air film cooling mode. The double-layer-wall heat insulation screen comprises a gas side gas film hole plate, a cool air side impacting plate and a trapezoidal reinforcing frame. The gas side air film hole plate serves as the inner wall of a cylinder body of the afterburner, the inner side of the gas side air film hole plate is provided with a main gas duct of the afterburner, the cool air side impacting plate and an outer wall surface form a cool air duct, and the trapezoidal reinforcing frame is arranged between the impacting plate and the air film hole plate. The double-layer-wall heat insulation screen is formed by the impacting plate, the air film hole plate and the trapezoidal reinforcing frame. Cooling air is made to form an air film on the gas side inner wall of the heat insulation screen, and heat load and gas flow losses are reduced. In addition, composite cooling is formed through inner convection cooling and outer air film cooling of a double-layer wall, incoming heat is brought away through convection heat exchange, and the cool air utilization rate is increased. Reduction is achieved after reflection, the effect of vibration prevention is achieved, the service life of the afterburner is prolonged, and the reliability of the afterburner is enhanced.

Description

technical field [0001] The invention belongs to the field of gas turbine engines, and in particular relates to a double-wall heat shield for an afterburner. Especially suitable for afterburner of gas turbine engine, also suitable for main combustion chamber of gas turbine engine. Background technique [0002] The afterburner is generally used in military aviation jet engines. It is located between the turbine and the tail nozzle. It can obtain additional higher thrust by performing secondary fuel injection combustion on the gas generated in the main combustion chamber and passed through the turbine. [0003] Since the gas inlet temperature of the afterburner has reached 950-1000K, the temperature of the gas after afterburner can reach more than 2000K, and the afterburner usually works for a short time, so not only the cooling at extremely high working temperature must be considered, but also The thermal stress and thermal deformation of the cylinder material should be consi...

AI Technical Summary

Problems solved by technology

Although the divergent cooling heat shield structure has spoiler columns to enhance the heat exchange on the cold air side, the fluidity of the cold air is poor, and the cooling potential of the cold air cannot be fully utilized, and its cooling efficiency cannot meet the demand for reducing the amount of cold air.

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