Numerical Simulation Of High-speed Flows Research Articles

Software Package HySol for the Numerical Simulation of High-Speed Flows

Software Package HySol for the Numerical Simulation of High-Speed Flows

Numerical Simulation of High-Speed Flows Using the Algebraic Reynolds Stress Model

A turbulence model for high-speed compressible flows is developed. It is based on modeling the rapid and slow parts of pressure-strain correlation depending on gradient Mach number and on the assumption that the velocity fluctuations normal to streamlines play a key role in turbulent mixing process. It is shown that an increase in the flow velocity leads to a slowing of turbulent mixing and an increase in the anisotropy of the flow. Comparison of the calculation results with the available experimental data showed good agreement.

A high-order multi-zone cut-stencil method for numerical simulations of high-speed flows over complex geometries

In this paper, we present a method for performing uniformly high-order direct numerical simulations of high-speed flows over arbitrary geometries. The method was developed with the goal of simulating and studying the effects of complex isolated roughness elements on the stability of hypersonic boundary layers. The simulations are carried out on Cartesian grids with the geometries imposed by a third-order cut-stencil method. A fifth-order hybrid weighted essentially non-oscillatory scheme was implemented to capture any steep gradients in the flow created by the geometries and a third-order Runge–Kutta method is used for time advancement. A multi-zone refinement method was also utilized to provide extra resolution at locations with expected complex physics. The combination results in a globally fourth-order scheme in space and third order in time. Results confirming the method's high order of convergence are shown. Two-dimensional and three-dimensional test cases are presented and show good agreement with previous results. A simulation of Mach 3 flow over the logo of the Ubuntu Linux distribution is shown to demonstrate the method's capabilities for handling complex geometries. Results for Mach 6 wall-bounded flow over a three-dimensional cylindrical roughness element are also presented. The results demonstrate that the method is a promising tool for the study of hypersonic roughness-induced transition.

Numerical simulations of high-speed flows about waveriders with sharp leading edges

A procedure is developed for the numerical simulation of stagnation-free inviscid supersonic and hypersonic flows about waveriders with sharp leading edges. The numerical approach involves the development of a specialized grid generator (named HYGRID), an algebraic solution-adaptive grid scheme, and a modified flow solving method. A comparison of the results obtained for several waverider geometries with exact solutions, other numerical solutions, and experimental results demonstrated the ability of the new procedure to produce stagnation-free Euler solutions about sharp-edged configurations and to describe the physics of the flow in these regions.