Investigation of the Effect of Diverter on Air Intake Performance with CFD Analyses
Fighter jets can face serious problems during flight. One such problem is turbulent air entering the air intake and the resulting boundary layer during flight. To prevent these issues and increase engine performance, a diverter is designed and used. The diverter is a component placed between the body and engine and evacuate highly turbulent air away from the engine before it is taken in. This study aims to calculate and analyze the most commonly used Channel Type Boundary Layer Diverter, which covers both internal and external flow, in supersonic aircraft due to its high-performance, high-pressure recovery, and low weight requirements. The F-22 Raptor fighter plane was selected for analysis. The geometry of the aircraft up to the air intake was obtained, and analysis was conducted using the Ansys-Fluent program at a speed of M=0,8 to determine the boundary layer thickness. The height of the diverter was adjusted based on the obtained boundary layer thickness. Models with diverter and diverterless were created in 3D, and computational fluid dynamics (CFD) analyses were conducted to examine motor performance parameters. These analyses were conducted at speeds of M=0,8, M=1,2, and M=1,6 at an altitude of 30,000 ft. To correctly resolve the boundary layer section and ensure that the SST-kw turbulence model works correctly, the y+ value was kept below 1. Additionally, a transition mesh structure was created to detect the viscous region. Independence studies were conducted under flow volume-defined boundary conditions. The values obtained were compared with similar studies in the literature to evaluate their accuracy. The results showed that the diverter reduced drag coefficient and boundary layer thickness while increasing mass flow rate and pressure recovery.