Direct numerical simulation is used to study a round turbulent jet in a laminar crossflow. The ratio of bulk jet velocity to free-stream crossflow velocity is 5.7 and the Reynolds number based on the bulk jet velocity and the jet exit diameter is 5000. The mean velocity and turbulent intensities from the simulations are compared to data from the experiments by Su & Mungal (2004) and good agreem...

Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass from the surrounding cloud material. This process is investigated, using numerical models of molecular cloud dynamics. Molecular cloud regions without turbulent driving sources, or where turbulence is driven on large scales, exhibit rapid and efficient star formation in a clustered ...

We analyze wave propagation in turbulent media using the Gaussian white-noise approximation. We consider two rigorous Gaussian white-noise models: one for the wave field and the other for the Wigner distribution associated with the wave field. Using the white-noise model for the Wigner distribution we show that the interaction of a wave field with the turbulent medium can be characterized in te...

In this research, the performance of nonlinear k-ε turbulence model in resolving the time delay between mean flow changes and its proportionate turbulent dissipation rate adjustment was investigated. For this purpose, the ability of Launder-Spalding linear, Suga non-linear, Yakhot RNG and Rietz modified RNG k-ε models are compared in the estimation of axial mean velocity profile and turbulent i...

Turbulence structure on the gas side of a wavy stratified flow was experimentally investigated in a near horizontal 18.7 cm (H) 10 cm (W) 5.5m (L) rectangular duct.By applying the Variable Interval Time Averaging (VITA) technique to the hot wire anemometer measurements frequency of occurrence of turbulent events were detected near the air-water interface. Experimental results showed that fr...

T. Tsuji Y. Nagano Department of Mechanical Engineering Nagoya Institute of Technology, Nagoya, Japan l lA turbulent natural convection boundary layer along a vertical flat plate in air is investigated with hot-wire techniques. Profile measurements of mean velocity, mean temperature, and turbulent quantities, which are obtained well into the wall region, clarify some characteristics peculiar to...

The general consensus is that in order to reproduce the observed solar p-mode oscillation frequencies, turbulence should be included in solar models. However, until now there has not been any well-tested efficient method to incorporate turbulence into solar modeling. We present here two methods to include turbulence in solar modeling within the framework of the mixing length theory, using the t...

This paper proposes two DES (Detached Eddy Simulation) model and one hybrid RANS (Reynolds Averaged Navier-Stokes)/ LES (Large Eddy Simulation) model for the simulations of unsteady separated turbulent flows. The two-equation k-ε based models are implemented in a full 3-D Navier Stokes solver and simulations are carried out using a 3 order Roe scheme. The predictions of the models are compared ...

Large Eddy Simulation (LES) is performed to study the physiological pulsatile transition-to-turbulent non-Newtonian blood flow through a 3D model of arterial stenosis by using five different blood viscosity models: (i) Power-law, (ii) Carreau, (iii) Quemada, (iv) Cross and (v) modified-Casson. The computational domain has been chosen is a simple channel with a biological type stenosis formed ec...

Flow characteristics are presented of simulation results of plane impinging jets at high nozzle-plate distances, with two k-ω based hybrid RANS/LES (Reynolds Averaged Navier–Stokes/Large–Eddy Simulation) models and a k-ω RANS model. The first hybrid RANS/LES model is obtained by substitution of the turbulent length scale by the local grid size in the destruction term of the turbulent kinetic en...