Design of hypersonic inward turning inlets with controllable Mach number distribution

Abstract

A method has been devised for the design of hypersonic inward turning inlets. On condition that the Mach number distribution along the surface of basic flowfield had been given, this method applied the rotational method of characteristics to design axisymmetric flowfield and streamtracing techniques to generate an invisid configuration, and then designed final inlets with viscous correction. Five typical kinds of basic flowfields designed under same constraints had been investigated. Complete design procedure was described based on the law of arc tangent Mach number distribution, and the characteristics of a hypersonic inward turning inlet with circular shape entrance were studied through number simulation. The results indicate that, there is a biggish diversity between Mach numerical distributions and its corresponding law of pressure rise; Busemann basic flowfield is very similar to constant Mach number gradient distribution; the basic flowfield with arc tangent Mach number distribution has the best general performance; the Mach number distribution on streamlines of the surface of inlets dovetails well with basic flowfield; this kind of inlet has a good performance and its general performance is roughly equivalent to an inlet with controlled pressure gradient at design point. Nomenclature CRI= internal contraction ratio of inlet CRT = total contraction ratio of inlet Ma = Mach number Ma r = Mach number on the wall behind leading shock wave a, b, c = coefficient of arc tangent curve c 1 , c 2 , c 3 = coefficient of curve p = static pressure R = radius x = coordinate direction = compression angle of leading edge = total pressure recovery coefficient Subscripts 0 = free stream c = center body e = exit plane i = intake plane th = throat plane

Research Progress of Hypersonic Inlet Inverse Design Based on Curved Shock Compression System

“…In earlier studies, the approximate inverse design method 23 based on the Prandtl-Meyer equation is used, and now the inverse design based on method of characteristics prevails. [26][27][28][29][30] The numerical simulation and wind tunnel test (Fig.11) showed feasibility of this method. 30 (a) Wind tunnel test model (b) Schlieren photograph of the flow field Figure 11.…”

“…The pattern of Mach number distribution is also extensively explored, such as law of constant Mach number gradient, quadratic curve, square root function, arctangent function, and piecewise function [26][27][28][29][30] are studied. The design according to combination of wall pressure and Mach number is also studied.…”