Direct Numerical Simulations (DNS) of turbulent zero pressure gradient boundary layers have been performed on two high performance computers with di erent architectures. The one, a Cray T3E-900, is a massively parallel computer (HLRS computing center, Stuttgart/Germany). The other, a Fujitsu VPP700, is a Vector-parallel computer (Leibniz Computing Center, Munich/Germany). Both computers are wel...

For almost four decades, Hill's "Model 4" [J. Fluid Mech. 88, 541 (1978) has played a central role in research and technology of optical turbulence. Based on Batchelor's generalized Obukhov-Corrsin theory of scalar turbulence, Hill's model predicts the dimensionless function h(κl(0), Pr) that appears in Tatarskii's well-known equation for the 3D refractive-index spectrum in the case of homogene...

A direct numerical simulation ~DNS! database is used to develop a model of subgrid-scale temperature fluctuations for use in large-eddy simulations of turbulent, reacting hypersonic flows. The proposed model uses a probability density representation of the temperature fluctuations. The DNS database reveals a physically consistent relation between the resolved-scale flow conditions that may be u...

In this paper, we have tested the parallel performance of an Intel Xeon-based Linux PC cluster using a finite element code for direct numerical simulation (DNS) of incompressible fluid turbulence. The parallel performance of the PC cluster, which used up to 64 2.8 GHz processors, was evaluated by comparing three scales of DNS trial runs consisting of 3.3, 5.8, and 10.1 million elements. Subrout...

The TSTC project is a multi-university collaborative effort to develop a high-fidelity turbulent reacting flow simulation capability utilizing terascale, massively parallel computer technology. The main paradigm of our approach is direct numerical simulation (DNS) featuring highest temporal and spatial accuracy, allowing quantitative observations of the fine-scale physics found in turbulent rea...

This paper focusses on three main numerical methods, i.e., the Reynolds-Averaged Navier-Stokes (RANS), Large Eddy Simulation (LES), and Direct Numerical (DNS) methods. The formulation variation of different RANS methods are evaluated. advantage disadvantage models to characterize turbulent flows discussed. progress LES with subgrid scale is presented. Special attention paid inflow boundary cond...

A new computational capability under development for accurate and efficient high-fidelity direct numerical simulation (DNS) and large eddy simulation (LES) of turbomachinery is described. This capability is based on an entropy-stable Discontinuous-Galerkin spectral-element approach that extends to arbitrarily high orders of spatial and temporal accuracy and is implemented in a computationally e...

Large-eddy simulation (LES) is performed to investigate the passive scalar development in a plane jet. This is a follow-up of our previous simulation of the jet  owŽ eld. The LES results are compared to both experiments and direct numerical simulation (DNS). Two subgrid models are investigated: the dynamic Smagorinsky model and the dynamic mixed model. It is found that the evolution of mean sc...

This article reports the results of research on application turbulent model to fluid flow in cavities. was developed using kinetic energy equation k, dissipation ɛ and temperature variance θ2 applying damping function f. While equations about tensor stress vector heat flux are formulated algebraically. simulation is carried out at Rayleigh number Ra = 5 x 1010. applied a three-dimensional cavit...

in this study, the dispersion mechanisms of aerosols suspended in a turbulent plane channel flow is investigated using a novel numerical approach. a turbulent channel flow is simulated by a direct numerical simulation (dns) method, for which no-slip boundary conditions are assumed at the top and bottom walls, while periodicity conditions are applied on the other sides. dns, in particular, allow...