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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.

A double shock waverider forebody configuration, with curved surfaces and known pressure fields and shock arrays, is constructed by a stream-tracing approach. The compression surface consists of a wedge and conical shocks. The conical shock results from a modified wave-derived bump surface that diverts the boundary layer before the inlet entrance. The design is fully computational fluid dynamics based and emphasis is placed on the compact design with boundary layer diverting ability. Controlling or diverting the thick boundary layer safely is a difficult challenge in hypersonic flight vehicle design especially when the inlets are highly integrated with the fuselage. Numerical simulations show that the new combination can divert a significant fraction of boundary layer before the inlet and maintains a good compression ratio for propulsion efficiency at Mach 5.0. Effects of forebody aerodynamics on the integrated inlet and comparisons with other systems are described in this paper.

Designing an inlet based on the fuselage geometry and its constraints is an important part of flight vehicle design. Among the different possible configurations, design integration of a supersonic inlet with a cylindrical fuselage is a major challenge. On one hand, propulsive efficiency requirements force the designers to consider the simplest compression surfaces for the inlet entrance geometries and on the other hand, the considerable drag of inlet/diverter integrations needs to be minimized, which can affect the inlet. In this paper, two new concepts as a replacement for a top mounted pitot inlet are presented: a three-dimensional wave-derived inlet and a trigonometric bump inlet. They are designed based on computational fluid dynamics simulations and their performance has been measured and compared with the initial single normal shock inlet as a baseline.

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Controlling and directing the boundary layer on the surfaces of a flight vehicle are two of the most demanding challenges in advanced aerodynamic designs. The design of highly integrated and submerged inlets with a large offset between the entrance and compressor face is particularly challenging because of the need for controlling or reducing the adverse effects of the boundary layer on propulsive efficiency. S-duct diffusers are used widely in flight vehicles when the compressor face needs to be hidden, and their performance is generally sensitive to the quality of ingested boundary layer from the fuselage. Passive or active flow control mechanisms are needed to prevent flow separations at the bends. In this paper, a new method is presented for optimal inlet/body integration based on a pair of ridges ahead of the inlet and its effects on the performance of a semicircular S-duct inlet integrated on a flat surface using CFD. In this design, the ridge changes an inefficient inlet concept to one with acceptable performance. The new method of integration is practicable for top-mounted inlet configurations where the use of diverters and other mechanisms results in higher amounts of drag, weight, and complexity.

This study describes the aerodynamic efficiency of a forebody–inlet configuration and computational investigation of a drone system, capable of sustainable supersonic cruising at Mach 1.60. Because the whole drone configuration is formed around the induction system and the design is highly interrelated to the flow structure of forebody and inlet efficiency, analysis of this section and understanding its flow pattern is necessary before any progress in design phases. The compression surface is designed analytically using oblique shock patterns, which results in a low drag forebody. To study the concept, two inlet–forebody geometries are considered for Computational Fluid Dynamic simulation using ANSYS Fluent code. The supersonic and subsonic performance, effects of angle of attack, sideslip, and duct geometries on the propulsive efficiency of the concept are studied by solving the three-dimensional Navier–Stokes equations in structured cell domains. Comparing the results with the available data from other sources indicates that the aerodynamic efficiency of the concept is acceptable at supersonic and transonic regimes.