The purpose of this paper is to studying nonlinear k-ε turbulence models and its advantages in internal combustion engines, since the standard k-ε model is incapable of representing the anisotropy of turbulence intensities and fails to express the Reynolds stresses adequately in rotating flows. Therefore, this model is not only incapable of expressing the anisotropy of turbulence in an engine c...

Sensitivity measurements performed on EVLA antenna #14 show that the cold-sky zenith system temperature is about 45K for the 18 – 26 GHz band, and 60 K for the low frequency end of the 40 – 50 GHz band, rising to 95 K at the high frequency end. Efficiency measurements based on the planet Venus show the antenna efficiency to be about 50% in the 18 – 26 GHz band, and about 28% for the 40 – 50 GHz...

in this paper, a two-dimensional reynolds averaged navier-stokes (rans) model is developed to simulate the shoaling, breaking and overtopping of a solitary wave over a vertical breakwater. turbulence intensity is described by using a k turbulence closure model and the free surface configuration is tracked by volume of fluid (vof) technique. to validate the numerical model the simulation result...

In this paper a new macroscopic k-ε model is developed and validated for turbulent flow through porous media for a wide range of porosities. The morphology of porous media is simulated by a periodic array of square cylinders. In the first step, calculations based on microscopic v2 − f model are conducted using a Galerkin/Least-Squares finite element formulation, employing equalorder bilinear ve...

Several rigorous turbulent models have been developed in the past years and it can be seen that more research is needed to reach a better understanding of their generality and precision by verifying their applications for distinct hydraulic phenomena; under certain assumptions. This survey evaluates the performance of Standard k-ε, Realizable k-ε, RNG k-ε, k-ω and RSM models in predicting flow ...

flow structure and heat transfer characteristics around two-equal in-tandem square cylinders in the two dimensional laminar and turbulent flow regimes are simulated numerically for reynolds and prandtl numbers, re=1-1×10 5 , pr=0.71, respectively. the investigation is based on an implicit finite volume scheme for integrating the unsteady navier-stokes equations and use of standard κ-ε model to ...