Experimental and numerical study of the cooling characteristics of the double-walled cooling structure on integral support plate

Abstract

The diffuser, rectifier, fuel injection rod, and flame holder in the afterburner are designed integrally, and a double-layer cooling structure is installed for the integral flame holder. Infrared thermography is employed to carry out the cooling efficiency test experiments under non-afterburner conditions, and the numerical simulation method is used to obtain the flow characteristics inside the integral afterburner. The effects of subtle geometrical parameter changes on the near-wall flow and wall-cooling effect are investigated. The results show that: The cooling air covers the film panel to form a film under the traction of the backflow vortex and spiral vortex behind the support plate, which provides effective cooling for the integral flame holder; the increase of the mass flow ratio will improve the cooling effectiveness of the double-wall, but it will cause additional pressure loss; impact spacing H has a small effect on the cooling effectiveness and relative pressure loss; reduced film aperture diameter df, increased aperture spacing S and aperture row angle β lead to a drop in the cooling capacity of the double-wall, whereas a reduced impact aperture diameter di leads to a certain degree of improvement in the cooling effectiveness of the double-wall.

Keywords

• Integral afterburner
• Double-wall
• Infrared thermography
• Cooling effectiveness
• PIV