A direct numerical simulation of a supersonic turbulent boundary layer has been performed. We take advantage of a technique developed by Spalart for incompressible ow. In this technique, it is assumed that the boundary layer grows so slowly in the stream-wise direction that the turbulence can be treated as approximately homogeneous in this direction. The slow growth is accounted for by a coordi...

An acoustic prediction capability for supersonic axisymmetric jets was developed on the basis of OVERFLOW Navier-Stokes CFD (Computational Fluid Dynamics) code of NASA Langley Research Center. Reynolds-averaged turbulent stresses in the flow fie ld are modeled with the aid of Spalart-Alimaras one-equation turbulence modeL Appropriate acoustic and outflow boundary conditions were implemented to ...

A time discretization scheme based on the third-order backward difference formula has been embedded into a Chebyshev tau spectral method for the Navier-Stokes equations. The time discretization is a variant of the second-order backward scheme proposed by Krasnov et al. (J. Fluid Mech., 2008). Highresolution direct numerical simulations of turbulent incompressible channel flow have been performe...

Numerical simulations are performed of the turbulent flow and thermal field in a structured porous media. The geometry of interest is an open lattice structure that is made up of mutually orthogonal, millimeter-scale, thermally conductive cylindrical elements. A large-eddy simulation (LES) is performed and the results are used as reference data to evaluate the performance of three commonly used...

Robust design optimization involves finding the loworder statistical moments, i.e. the maximization of some mean quantity of interest and minimization of its variance. The question arises as to when a mean or variance value can be considered to be converged to an acceptable level of certainty. A designer naturally seeks to keep the number of function evaluations as low as possible when convergi...

This paper presents computational results for two DES (Detached Eddy Simulation), one hybrid RANS (Reynolds Averaged Navier-Stokes)/ LES (Large Eddy Simulation) and some preliminary results from PANS (Partially Averaged Navier-Stokes) turbulence for simulation of unsteady separated turbulent flows. The models are implemented in a full 3-D Navier Stokes solver and are based on the twoequation k-...

From the simplest models to complex deep neural networks, modeling turbulence with machine learning techniques still offers multiple challenges. In this context, present contribution proposes a robust strategy using patch-based training learn turbulent viscosity from flow velocities, and demonstrates its efficient use on Spallart-Allmaras model. Training datasets are generated for past two-dime...