# Numerical Strategies for Compressible Turbulent Flows

Researcher:

**Ioannis Asproulias**

Supervisor(s): *Dr. A. Revell, Dr. T. Craft*

Sponsor:

Start Date: *January/2010* End Date: __

Keywords:

## Overall Research Aim

The aerospace and energy industry is in need for integrated supersonic simulations for both internal and external applications. Therefore, the full resolution of the flow through engines and intake ducts, the flow through rocket nozzles and jet thrust vectoring are of high interest. The most important feature of these flows is the presence of shock waves of different types, like normal, oblique and reflected ones. These flows are challenging from the numerical point of view, due to the presence of steep gradient regions in density, pressure and velocity around the shock and thus shock capturing is of fundamental meaning. Further physical modeling challenges arise from the interactions of turbulent boundary layers and separation regions, and thus the appropriate modeling of the turbulent Reynold stresses is essential. Therefore, the initial objective is an investigation on the performance of different compressible solvers (density-based,pressure-based) provided by

OpenFoam CFD package. A further investigation will be on the performance of different TVD convective schemes.

## Research Progress

## 1.Asymmetric Diffuser (Code_Saturne v1.3.3):

Different turbulence models are tested for their prediction of the separation region of the flow.

## 2.Shock Tube (OpenFoam v1.6):

The two families of compressible solvers (pressure-based, density-based) and different TVD convective schemes are compared.

In this test case the grid is aligned with the shock.

## 3.Current Work: Compression Ramp 24 deg for Mach = 2.9 (OpenFoam v1.6):

The main characteristic of this flow is the strong interaction of the shock with the separated turbulent boundary layer. In this

case, the grid is misaligned with the shock. Therefore, this flow is challenging from the numerical and turbulence modeling

point of view. The velocity field of an initial calculation using the k-ω SST model is shown below.

**Last Modification:**
r7 - 2010-12-08 - 07:01:20 -

IoannisAsproulias