A spatially non-dissipative, implicit numerical method to simulate turbulent reacting flows over a range of Mach numbers, is described. The compressible Navier–Stokes equations are rescaled so that the zero Mach number equations are discretely recovered in the limit of zero Mach number. The dependent variables are co-located in space, and thermodynamic variables are staggered from velocity in t...

A new compact active turbulence generator is developed, tested, and characterized, which extends the capabilities of such generators used in turbulent premixed combustion research. The composed two blades that resemble shape bow-ties. Hot-wire anemometry high-speed imaging are performed to characterize non-reacting flow produced by dynamics, respectively. Two mean bulk velocities 5.0 7.0 m/s ex...

The paper describes DNS of a jet in crossflow at Re=650 and jet-to-crossflow velocity ratio R=3.3. Laminar boundary conditions are employed which makes the present flow configuration advantageous for benchmarking. Use is made of local grid refinement in the region of transition to turbulence. Comparison with Re=325 is carried out for some appropriate quantities. Nine passive scalars, reacting a...

in this paper, analysis of fluid flow and heat transfer over the bank of tubes is considered. k-ω sst model is applied for simulation of turbulent flow. in this paper, the improvement of efficiency of a bundle of circular tubes by changing the shape of the cross section of one row of the pipes to the elliptical cross section as an innovative plan is considered. as know, friction factor in turbu...

The present article focuses on the evaluation of a first-moment closure model applicable to film cooling flow and heat transfer computations. The present first-moment closure model consists of a higher level of turbulent heat flux modeling in which two additional transport equations for temperature variance kθ and its dissipation rate εθ are ...

A methodology for solving unsteady premixed turbulent flame propagation problems in high Reynolds number (Re), high Damkohler number (Da) spatially evolving flows is developed. The method is based on Large-Eddy Simulation (LES) with a subgrid combustion model based on the Linear-Eddy Model (Kerstein, 1991). An inter-LES cell burning mechanism has been added to the present formulation to account...

It is now well established that quantities such as energy dissipation, scalar dissipation and enstrophy possess huge fluctuations in turbulent flows, and that the fluctuations become increasingly stronger with increasing Reynolds number of the flow. The effects of this small-scale “intermittency” on various aspects of reacting flows have not been addressed fully. This paper draws brief attentio...

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...

wall-jet flow is an important flow field in hydraulic engineering, and its applications include flow from the bottom outlet of dams and sluice gates. in this paper, the plane turbulent wall jet in shallow tailwater is simulated by solving the reynolds averaged navier-stokes equations using the standard  turbulence closure model. this study aims to explore the ability of a time splitting method ...

We report results of a Large Eddy Simulation (LES) effort of turbulent compressible nonpremixed reactive jets. It is well known that there are several difficulties associated with compressible reactive flows in comparison with incompressible flows. In incompressible flows, the energy and mass conservation (for constant density flows) equations are decoupled from the velocity field. Moreover, th...