Two combustion models for turbulent premixed combustion in the flamelet regime are developed for unsteady simulations. The first model is a convensional G equation flamelet model and the main issues discussed are the subgrid closure. The second model is based on the Linear-Eddy Model. Both models are used in simulation of turbulent stagnation point flames. The heat release and turbulence intens...

Stratified flows are prevalent in indoor and outdoor environments. To predict these flows, this investigation evaluated the performance of seven turbulence models by comparing the simulation results with the experimental data of both weakly and strongly stratified jets. The models tested included six Reynolds-Averaged Navier-Stokes (RANS) models and one Large Eddy Simulation (LES) model. The ve...

The mixing of transported scalars in turbulent flows is a classic topic in turbulence research. The “diffusing power” of turbulent flows was originally recognized, among others, by Taylor (1915) since the beginning of the last century. Later on, Taylor (1921, 1935) also provided the first statistical framework to predict turbulent diffusion in air streams, as well as the scalar mixing in pipe f...

Numerical simulation of the turbulent flow around a triangular cylinder at Reynolds number of 45,000 is presented in this paper. A body force potential model is used to model the turbulent motion. This approach is able to model non-equilibrium turbulence accurately at a cost and complexity comparable to k-ε models. The numerical method used in this calculation is an unstructured staggered mesh ...

This paper presents 2-D finite volume method for computation of viscous drag based on Reynolds-averaged Navier-Stokes (RANS) equations. Computations are performed on bare submarine hull DREA and six axisymmetric bodies of revolution with a number of length-diameter (L/D) ratios ranging from 4 to 10. Both structured and unstructured grids are used to discretize the domain around the bodies. Diff...

The thermal confinement time of a magnetized fusion plasma is essentially determined by turbulent heat conduction across the equilibrium magnetic field. To achieve the study of turbulent thermal diffusivities, Vlasov gyrokinetic description of the magnetically confined plasmas is now commonly adopted, and offers the advantage over fluid models (MHD, gyrofluid) to take into account nonlinear res...

In this paper, we address the problem of how to account for second-order statistics of turbulent flows using low-complexity stochastic dynamical models based on the linearized Navier–Stokes equations. The complexity is quantified by the number of degrees of freedom in the linearized evolution model that are directly influenced by stochastic excitation sources. For the case where only a subset o...

The objective of this study is to improve Eulerian-Eulerian models of particle-laden turbulent flow. We begin by understanding the behavior of two existing models—one proposed by Simonin von Kármán Institute of Fluid Dynamics Lecture Series, 1996 , and the other by Ahmadi Int. J. Multiphase Flow 16, 323 1990 —in the limiting case of statistically homogeneous particle-laden turbulent flow. The d...