Numerical Simulation of Aero Engine Active Clearance Control with Flanged Compressor Casing Structure

Compared to the well-established high-pressure turbine active clearance control technology, research on active clearance control for compressors remains relatively insufficient. Therefore, this study proposed an impingement cooling pipeline design with a flanged casing structure for active clearance control (ACC) in the last stage of an aero engine compressor, and investigated the influence of flange structural parameters on cooling performance through numerical simulations. Using a fluid-thermal-structural coupling approach, the distribution of Nusselt number (Nu) on the outer casing surface and radial deformation of the inner casing surface were analyzed under different flange width-to-height ratios (b/h). The results demonstrate that increasing the flange width-to-height ratio enhances forced convective heat transfer on the outer casing surface. When the flange width is reduced, the casing contraction increases by 75%, but the increased thermal resistance simultaneously inhibits heat conduction efficiency within the casing, thereby affecting deformation response. The findings reveal the influence patterns of flange structural parameters on impingement cooling pipeline performance, providing valuable references for optimizing compressor active clearance control systems.