The process of star formation in interstellar molecular clouds is believed to be controlled by driven supersonic magnetohydrodynamic turbulence. We suggest that in the inertial range such turbulence obeys the Kolmogorov law, while in the dissipative range it behaves as Burgers turbulence developing shock singularities. On the base of the She–Lévêque analytical model we then predict the velocity...

A thermohydrodynamic (THD) analysis of turbulent flow in journal bearings is presented based on the computational fluid dynamic (CFD) techniques. The bearing has infinite length and operates under incompressible and steady conditions. In this analysis, the numerical solution of Navier-Stokes equations with the equations governing the kinetic energy of turbulence and the dissipation rate, couple...

This paper presents a numerical study of heat transfer to turbulent and laminar Cu/water flow over a backward-facing step. Mathematical model based on finite volume method with a FORTRAN code is used to solve the continuity, momentum, energy and turbulence equations. Turbulence was modeled by the shear stress transport (SST) K–x Model. In this simulation, three volume fractions of nanofluid (0%...

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 freque...

The lag model proposed by Olsen and Coakley is applied in combination with the baseline k–! two-equation turbulence model to simulate the steady and unsteady transonic  ows in a diffuser. A fully implicit time-accurate multigrid algorithm is used to solve the unsteady Navier–Stokes equations and the coupled k–! turbulence model equations. Two test cases are investigated, one with a weak shock ...

Turbulence closure models are evaluated for application to spilling and plunging breakers in the surf zone using open source computational fluid dynamics software. A new library of turbulence models for application to multiphase flows has been developed and is assessed for numerical efficiency and accuracy by comparing against existing laboratory data for surface elevation, velocity and turbule...

The objective of this paper is the numerical study of the flow through an axial fan and examining the effects of blade design parameters on the performance of the fan. The axial fan is extensively used for cooling of the electronic devices and servers. Simulation of the three-dimensional incompressible turbulent flow was conducted by numerical solution of the (RANS) equations for a model. The S...

In this study, the heat transfer and flow characteristics for cube circular hollow models in channels with cross flow-impinging jet were numerically investigated by using water 2% CuO-Water nanofluid. The numerical work was carried out steady three-dimensional Ansys-Fluent program k-? turbulence model. A fin 45? 90? angles D, 1.166D, 1.333D (K) lengths added to upper channel surface from imping...

The aim of this paper is numerical and experimental study of the effects of flow hydraulics, pipe structure (particularly elastic behaviour) and submerged jet on leak behaviour. In this regard, experimental tests were performed on a high-pressure circulation set up. Experiments were performed on an old steel pipe and a High Density Polyethylene (HDPE) pipe discharged to the atmosphere in a wide...