This paper reports a study on the effect of helical, spiral, and helical-spiral combination manifold configuration on air motion and turbulence inside the cylinder of a Direct Injection (DI) diesel engine motored at 3000 rpm. Three-dimensional model of the manifolds and the cylinder is created and meshed using the pre-processor GAMBIT. The flow characteristics of these engine manifolds are exam...

in the present work a two dimensional numerical investigation of steam flows in a turbine blade passage is performed. a finite volume approach has been used and the pressure–velocity coupling is resolved using the simple algorithm. the purpose of this paper is to find that one of the used turbulent models is better for this kind of studies. a structured mesh arrangement with boundary layer mesh...

The paper considers the problem of selecting a turbulence model to simulate natural convection near surface VVER-1000 fuel assembly unloaded from reactor by computational fluid dynamics (CFD simulation) methods. is selected comparing calculated data obtained using Ansys Fluent software package with results experimental studies on heated vertical plate immersed in water, which simulates side fac...

The rotation speed of water at the inlet low hump outlet conduit has a great effect on its hydraulic performance. Therefore, influence different speeds loss and flow pattern is studied in this paper. By solving RANS equations RNG k-ε turbulence model, 3D field were calculated under speeds. To verify numerical results, model tests with guide vanes conducted. results show that along growth speed,...

Intense fluid-dynamic interaction at the impeller outlet strongly affects unsteady flow and pressure stability within centrifugal pump. In order to have a better understanding of fluctuation pumps, numerical calculation is carried out by using RNG k-epsilon turbulence model under various rates. The results are compared with experimental in verify reliability model. amplitude frequency distribut...

The unsteady and random character of turbulent flow motion is a key aspect of the multidimensional modeling of internal combustion engines (ICEs). A typical example can be found in the prediction of the cycle-to-cycle variability (CCV) in modern, highly downsized gasoline direct injection (GDI) engines, which strongly depends on the accurate simulation of turbulent in-cylinder flow structures. ...

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...

The spacer grid has a significant impact on the thermal-hydraulic characteristics of rod bundle channel, which directly determines possibility boiling crisis. multi-phase flow model coupling is proposed to acquire secondary and void fraction for subcooled in fuel assembly. Compared with experimental data, RNG k–ε turbulence selected current research. In addition, parameters 5 × are studied focu...

A numerical investigation into the particle-turbulence interaction behaviour of dilute gas-particle flows over a backward-facing step geometry is reported. An Eulerian two-fluid model with additional turbulence transport equations for particles is employed. RNG based k-ε model is used as the turbulent closure wherein additional transport equations are solved to better represent the combined gas...