Optimal shock wave parameters for supersonic inlets

Abstract

Nomenclature M= Mach number n = total number of shock waves in the system /?, p 0 = static, stagnation pressure S = ratio of the overall total pressure ratio for an /z-shock-wave system to the total pressure ratio for case with a single shock j8 = shock-wave inclination 8= flow deflection f, = ratio of static pressures, p l + l lpi Subscripts i'(l, 2, . . /,* , n) -number of the shock in the system = number of iteration step = limiting value for n -> o°I ntroduction T HE effectiveness of supersonic inlets is strongly influenced by the unavoidable presence of shock waves. At high supersonic speeds it is desirable to design inlets with multiple-shock configuration in order to maximize the pressure recovery. The theory of shock waves is based on the assumption of discontinuity in flow parameters across the shock surface and the requirement that the principles of conservation of mass, momentum, and energy across this surface be satisfied. This approach results in shock relations, which when combined with a pressure recovery criteria, yields values of the shock parameters corresponding to the optimal shock configuration. In the principal work by Oswatitsch 1 the optimization problem is formulated for ^-shock-wave system n -I of these being oblique shocks and the last one a normal shock wave. The task set forth is to determine, for a given n and an upstream Mach number M l9 the shock configuration producing the maximum overall total pressure ratio p 0 /i + i/PoiThe solution to this problem yields 6,-. It is possible to formulate the optimization problem for n oblique shock waves

Theoretical Design and Computational Fluid Dynamic Analysis of Projectile Intake

“…Researchers' studies and experiments have confirmed the theoretical operation and demonstrated the feasibility of the twodimensional inlet as an air supply system that meets those desires. The previous studies by some institutions at home and abroad revealed the potential to provide efficient and flexible airflow which the combustion requires [1][2].This interest in the supersonic projectile inlet encouraged our research team to proceed with design and verification of a new one. This paper's study is carried out as a part of the wide research on solid rocket ramjet extended range projectile.…”

Optimization design for the two-dimensional contour of the ramjet engine inlet

“…The engine used in projectile is composed of inlet, gas generator, secondary firebox and nozzle. The function of the ramjet engine inlet is to switch the kinetic energy to potential energy and raise the pressure of the gas stream using the velocity in front of it, and provide the airflow the engine needed [1]- [3]. The application research of the inlet used in aero engine is mature, but there are also some tasks to research in applying it on the ramjet assisted projectile.…”