A waverider is a hypersonic vehicle configuration designed in such a way that the shock wave emanating from the vehicle itself stays attached to the vehicle’s leading edge, providing several benefits[1]: (a) the shock separates the flow filed on the upper surface from the flow field on the lower surface of the vehicle, therefore no spillage of high-pressure flow takes place from the lower to the upper surface at the tip; (b) the uniform flow on the lower surface is ideal for entering a scramjet engine; (c) the geometry configuration of the waverider can be achieved through an inverse design methodology from a known flow filed around a conical geometry. Such a methodology will be used in the following sections of this work.

[1] D.R. Sandlin, and D.N. Pessin, Aerodynamic Analysis of Hypersonic Waverider Aircraft, NASA-CR-192981, 1993.

The DSMC (Direct Simulation Monte Carlo) method was pioneered by Graeme Bird in the late 1960s[1]. This technique is a particle-based statistical approach designed for the analysis of rarefied flows by simulating the behavior of particles, representing a fraction of the actual molecules in the flow field, without solving equations explicitly. The method involves uncoupling the motion of these simulated particles and calculating intermolecular collisions over small time intervals. It has been mathematically demonstrated that, for a large number of particles per cell, the DSMC method converges to the Boltzmann equation[2].

[1] G.A. Bird, Molecular gas dynamics and the direct simulation of gas flows, Clarendon Press, Oxford, 1994.

[2] W. Wagner, “A convergence proof for Bird’s direct simulation Monte Carlo method for the Boltzmann equation”,in Journal of Statistical Physics, 66, pp. 1011-1044, 1992.