Numerical Simulations of Busemann Hypersonic Inlets At Finite Flight Angles

摘要

Complete axisymmetric Busemann inlet bodies with a design Mach number of 6.0 were numerically simulated by the solution of the Euler equations at off-nominal pitch/yaw angles ranging up to 9°. The inviscid flow solutions are presented graphically, and performance parameters at the throat including pressure recovery, static temperature ratio, static pressure ratio, and adiabatic compression efficiency, are found for each flight condition. Simple statistical measures are used to obtain some indications of distortion level at the throat. Compared to the ideal conceptual Busemann inlet, an inlet with a finite leading edge attached to the Busemann compression surface is approximately 10% lower in adiabatic efficiency. Further, when the inlet is turned by 3°, the compression efficiency decreases again by nearly 10%. At a 6° flight angle, the adiabatic compression efficiency drops to a mere 42%. When the inlet is finally turned to 9°, it ceases to meaninngfully function as an inlet and simple computations for the efficiency give unphysical results. Graphical and tabular presentations of the flow solutions for each case are provided and discussed.