Both RaNS (Reynolds-averaged Navier-Stokes) and DES (Detached Eddy Simulation) type turbulence models were used in conjunction with a two-fluid model of bubbly flow and a new subgrid air entrainment model to predict air entrainment and transport in a hydraulic jump. It was found that the void fraction profiles predicted by both methods are in agreement with the experimental data in the lower sh...

New methods of flow visualization near absolute zero have opened the way to directly compare quantum turbulence (in superfluid helium) to classical turbulence (in ordinary fluids such as air or water) and explore analogies and differences. We present results of numerical simulations in which we examine the statistics of the superfluid acceleration in thermal counterflow. We find that, unlike th...

In this paper, the effect of air turbulence intensity on the flame structure in various radii and lengths of a flame holder numerically studied. Finite volume method is used to solve the governing equations. The obtained numerical results using realizable k-ε and β-PDF models show a good agreement with the experimental data. The results show that flame holder with greater lengths yield shorter ...

Autoignition of a hydrogen-air scalar mixing layer in homogeneous turbulence is studied using direct numerical simulation (DNS). An initial counterflow of unmixed nitrogen-diluted hydrogen and heated air is perturbed by two-dimensional homogeneous turbulence. The temperature of the heated airstream is chosen to be 1100 K, which is substantially higher than the crossover temperature at which the...

For many years, spatial and temporal inhomogeneities in precipitation fields have been studied using scanning radars, cloud radars, and disdrometers, for example. Each measurement technique has its own advantages and disadvantages. Conventional profiling radars point vertically and collect data while the atmosphere advects across the field of view. Invoking Taylor’s frozen turbulence hypothesis...

Several years ago, it was established by the work of P. W. Kadlec of Eastern Airlines (Project TRAPCAT, Ref. 1), that clear air turbulence was frequently associated with temperature gradients or discontinuities in the atmosphere. Barnes Engineering Company had just completed the development of the Satellite Infrared Spectrometer (SIRS) for the Weather Bureau for remote atmospheric temperature p...

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Stepped chute flows are characterised by intense turbulence and strong flow aeration (Fig. 1), but most studies did not investigate the turbulence characteristics. Detailed air-water flow properties were measured in skimming flow on a stepped chute (θ = 16o, h = 0.05 m). Longitudinal oscillations of depth-averaged flow properties were observed with a wave length of about two step cavity lengths...