Hypersonic viscous flow over large roughness elements

Transition of hypersonic flow past flat plate with roughness elements

Roughness elements in high speed flows can cause laminar-turbulent transition leading to higher heating rates and drag. Transition of flow past a hemispherical bump placed on a flat plate is explored in this paper for three Mach numbers [3.37, 5.26, 8.23] using direct numerical simulation on unstructured grids. The simulation parameters are chosen to match the experiments carried out by Danehy ...

Direct Numerical Simulation of Hypersonic Flow over a Blunt Cone with Axisymmetric Isolated Roughness

The ability of a finite roughness element to suppress the hypersonic second-mode instability on a cone is explored. A new code for simulating discrete roughness using a body-fitted grid over an analytic shape is developed. Linear stability analysis is performed on the Mach 8 meanflow of a 7◦ half-angle straight cone. The resulting N-factor analysis determines the second-mode frequency of 240 kH...

Numerical Simulation of Surface Roughness Effects on Receptivity of Hypersonic Flow Over Blunt Cones

The accurate prediction of laminar-turbulent transition in hypersonic boundary layers is a critical part of the aerodynamic heating analyses on hypersonic vehicles. Despite decades of extensive research, the prediction of hypersonic boundary-layer transition is still mostly based on empirical correlation methods or the semi-empirical n e method because a number of physical mechanisms leading to...

A multidimensional gas-kinetic BGK scheme for hypersonic viscous flow

This paper concerns the development and application of a gas-kinetic scheme based on the Bhatnagar–Gross–Krook (BGK) model for the Navier–Stokes equations in the study of hypersonic viscous flow. Firstly, we extend the gas-kinetic Navier–Stokes solver [K. Xu, A gas-kinetic BGK scheme for the Navier–Stokes equations and its connection with artificial dissipation and Godunov method, J. Comput. Ph...

Perspectives on Hypersonic Viscous and Nonequilibrium Flow Research