Design and performance study of a parametric diverterless supersonic inlet

Abstract

Diverterless supersonic inlet integration for a flight vehicle requires a three-dimensional compression surface (bump) design with an acceptable shock structure and boundary layer diversion; this results in a low drag induction system with acceptable propulsive efficiency. In this investigation, a computational fluid dynamics-based-generated bump is used to design an integrated diverterless supersonic inlet without any bleed mechanism on a forebody with a large wetted area. Numerical solution of the Navier–Stokes equations simulates the flow pattern of the configuration. The forebody design analysis includes simulating the effects of angle of attack and sideslip by dependent computational domains. Results demonstrate the ability of the bump surface to keep the shock structures in an operational mode even at high supersonic angles of attack. Analysis of shock structures and shock wave boundary layer interactions at supersonic maneuver conditions indicate that the aerodynamic efficiency of the diverterless supersonic inlet in conditions with a thick boundary layer and high angles of attack is sufficient to ensure operation throughout the supersonic flight envelope.

The inlet flow structure of a conceptual open-nose supersonic drone

“…The efficiency of the entrance geometry in capturing the streamtube at subcritical mode is compared in Figure 8 which shows that the wave-derived diffuser captures a higher mass over the ramped inlets without side walls or diverterless supersonic inlets (DSIs) which function based on subsonic flow spillage. 38,39 For this comparison, the AIP mean Mach number is around 0.44-0.47 for all cases. The captured mass flow ratio is defined as the rate of flow passing through the AIP face divided by the reference capture flow rate…”

“…Also, the proofs about the ability of the selected turbulence model in predicting the effect of adverse pressure gradient on the boundary layer inside the duct can be found in recent researches related to the flow structure of supersonic inlets. 37,38 Results and discussions Supersonic performance assessment At the design speed, the compression surface of WDONF generates the shock waves which compress the supersonic flow as was predicted analytically. Figure 7(a) illustrates the shock waves by the Mach contours on the plane of symmetry at subcritical operation modes.…”

“…The final grid for subsonic flow simulations of the inlet contains about 6.3 million cells to capture more detailed flow separation after the lip. Comparing the grid generation approach and the applied cell density for current geometries with the similar CFD studies [36][37][38] can help to measure the quality of the generated computational domains. Also, the proofs about the ability of the selected turbulence model in predicting the effect of adverse pressure gradient on the boundary layer inside the duct can be found in recent researches related to the flow structure of supersonic inlets.…”

“…The crosssectional Mach contours in Figure 14 The propulsive efficiency of WDONF is compared with 1/6.7-scale forebody/inlet of F-16 42 and a generic side-mounted diverterless supersonic inlet (DSI) from Ref. (38) in Figure 15(a)-(d). Figure 16(a) and (b) demonstrates the AIP flow structures by total pressure ratio contours.…”

Design and optimization of bump (compression surface) for diverterless supersonic inlet

“…[10][11][12] Owing to its superior design, DSI has been regarded as a favorable choice for several modern supersonic jet aircraft. 13 The generation of bumped surface requires a modern and robust design methodology as it needs to actively divert the upstream BL while maintaining the pressure recovery with minimum drag spillage. Stream tracing technique can be considered as one of the generation methods for bump alternatively known as raised compression surface.…”