An analysis of developing and fully developed turbulent flow was carried out when different techniques have been used in a zone close to the solid wall. In this paper, wall element technique based on the finite element method (FEM) has been adopted and compared with other techniques for determination of confined turbulent flow with a one equation model used to depict the turbulent viscosity is ...

We describe the first DNS-based measurement of the complete mean response of a turbulent channel flow to small external disturbances. Space-time impulsive perturbations are applied at one channel wall, and the linear response describes their mean effect on the flow field as a function of spatial and temporal separations. The turbulent response is shown to differ from the response a laminar flow...

In this paper, we present a knowledge-assisted approach for studying turbulent combustion simulation data. To understand the dynamic mechanisms of extinction and reignition in turbulent flames, scientists need to validate known relationships and reveal hidden ones among multiple variables. Based on the domain knowledge and questions posted by the scientists, we have designed an algorithm that h...

We periodically modulate a turbulent wind-tunnel flow with an active grid. We find a resonant enhancement of the mean turbulent dissipation rate at a modulation frequency which equals the large-eddy turnover rate. Thus, we find the best frequency to inject energy into a turbulent flow. The resonant response is characterized by the emergence of vortical structures in the flow and depends on the ...

An energy conserving model of MHD turbulence is described that predicts both mode coupling and turbulent dissipation. The dissipation takes the form of anomalous resistivity and viscosity due to turbulent magnetic fields. The model predicts a dualcascade of energy to large wave numbers and magnetic flux to small wave numbers. Turbulent rearrangement of equilibrium magnetic shear gene rates reso...

Related Articles Light attenuation experiments on double diffusive plumes and fountains Phys. Fluids 24, 066605 (2012) The geometry of inertial particle mixing in urban flows, from deterministic and random displacement models Phys. Fluids 24, 063302 (2012) Direction of scalar transport in turbulent channel flow Phys. Fluids 23, 115105 (2011) Turbulent diffusion in tall tubes. I. Models for Rayl...

A number of Grand Challenge applications are capable of generating such large quantities of data that data output may affect the applications performance. An example of such an application is modeling of turbulent convection. One means of dealing with this situation is data compression. This thesis examines applying wavelet based lossy compression techniques to turbulent convection data. It als...

Based on scaling arguments the governing equations for turbulent flows are classified. The similarity for stratified and rotating flows is characterized and the conditions for a hydrostatic assumption are shown for several flow regimes. For stratified rotating flow a scale analysis of the turbulent stresses exhibits different classes of second order closure. The complete sets of the governing e...

Particles with different density from the advecting turbulent fluids cluster due to the different response of light and heavy particles to turbulent fluctuations. This study focuses on the quantitative characterization of the segregation of dilute polydisperse inertial particles evolving in turbulent flow, as obtained from direct numerical simulation of homogeneous isotropic turbulence. We intr...

The results from direct numerical simulations of a spatially evolving super sonic at plate turbulent boundary layer ow with free stream Mach number of are presented The simulated ow eld extends from a transition region initiated by wall suction and blowing near the in ow boundary into the fully turbulent regime Distributions of mean and turbulent ow quantities are ob tained and an analysis of t...