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...

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 ...

One of the well-known properties of turbulent, premixed flames is that their speed of propagtion is correlated to the intensity of the turbulence they encounter. A simple consequence is that these types of flames are inherently unstable. Given a source of turbulence, if the flame is propagating faster than the mean flow, it will drift upstream and encounter increased turbulent intensities that ...

Turbulent mixed convection of a nanofluid (water/Al2O3, Φ=.02) has been studied numerically. Two-phase mixture model has been used to investigate the effects of nanoparticles mean diameter on the flow parameters. Nanoparticles distribution at the tube cross section shows that the particles are uniformly dispersed. The non-uniformity of the particles distribution occurs in the case of large nano...

A pressure-based implicit procedure to solve the Euler and Navier-Stokes equations on a nonorthogonal mesh with collocated finite volume formulation is described. The boundedness criteria for this procedure are determined from Normalized Variable diagram (NVD) scheme.The procedure incorporates the ε−k eddy-viscosity turbulence model. The algorithm is tested for inviscid and turbulent transonic ...

to enhance the understanding of the impact of obstacle buildings on pollution transportationand dispersion in the atmospheric boundary layer, it is necessary to know the atmospheric flow characteristics over terrains. wind flow characteristics in a boundary layer over a step-shaped cliff topography model with rough and smooth surfaces were studied numerically using computational fluid dynamics ...

This paper investigates the characteristics of wall pressure fluctuations in naturally developing boundary layer flows on axisymmetric bodies experimentally. The axisymmetric body has a modified ellipsoidal blunt nose. Flush-mounted microphones are used to measure the wall pressure fluctuations in the boundary layer flow over the body. The measurements are performed in a low noise wind tunnel. ...

An oscillating grids turbulence generator was constructed for studies of two new effects associated with turbulent transport of particles, turbulent thermal diffusion and clustering instability. These effects result in formation of large-scale and small-scale inhomogeneities in the spatial distribution of particles. The advantage of this experimental set-up is the feasibility to study turbulent...

The present paper is primarily concerned with modeling complex turbulent wall-bounded flow in spray-painting processes by using a commercial CFD code. Computational results of turbulent channel flow with low Reynolds numbers are compared with DNS data in order to obtain the performance of turbulence models and near wall treatments. The realizable k-ε model with the nonequilibrium wall function ...

[1] The reaction kinetics of submicron oleic (9-octadecanoic (Z)-) acid aerosols with ozone was studied using a novel aerosol mass spectrometric technique. In the apparatus a flow of size-selected aerosols is introduced into a flow reactor where the particles are exposed to a known density of ozone for a controlled period of time. The aerosol flow is then directed into an aerosol mass spectrome...