Design Factors for Two-Dimensional, External-Compression Supersonic Inlets

Abstract

Geometric and aerodynamic design factors were studied for the design of two-dimensional, external-compression inlets operating at a freestream Mach number of Mach 1.7. Computational simulations of the inlet flows were performed to obtain the inlet performance metrics consisting of the inlet flow rates, total pressure recovery, and total pressure distortion at the engine face. The key design factors identified included the external diffuser Mach number, cowl lip interior angle, bleed slot length, throat section aft centerbody slope, and subsonic diffuser length. Using the results of the Mach 1.7 inlet study, inlets were designed for Mach 1.4 and 2.0. The results provide useful insight on the significance of the design factors for the design of such inlets for commercial supersonic aircraft.

Aerodynamic Instabilities in High-Speed Air Intakes and Their Role in Propulsion System Integration

“…These aspects can significantly impact the overall intake performance, and flow behavior can vary depending on the intake's characteristics. Several studies have explored design optimization [45][46][47], while others have investigated how various intake configurations perform at off-design conditions or how different flow control methods can be used to prevent flow unsteadiness. These studies share a common goal: to widen the operational range and increase the efficiency of high-speed intakes.…”

“…With a small cowl deflection, the shock can be weakened, and the flow separation suppressed, possibly improving intake performance [52]. The design optimization of the cowl lip is more commonly investigated in steady flows, and any alterations can notably influence cowl drag, mass-capture, heat loads, and total pressure recovery [9,46,47,[53][54][55][56]. While Fisher [33] discussed various oscillation amplitudes with varying cowl lip positions during intake buzz, Shi et al [57] described the buzz evolution process influenced by the translation of the cowl.…”