Flash Boiling atomization is one of the most effective means of generating a fine and narrow-dispersed spray. Unless its complexity its potential has not been fully realized. In This Paper, a three dimensional chamber has been modeled with a straight fuel injector. Effect of Flash Boiling has been investigated by computational fluid dynamics (CFD) techniques. A finite volume approach with the ...

In this article, a Ranque–Hilsch Vortex Tube has been optimized utilizing axial angles for nozzles. Effect of nozzles angles on the flow behavior has been investigated by computational fluid dynamics (CFD) techniques. A finite volume approach with the standard k–ε turbulence model has been used to carry out all the computations. The dimensions of studied vortex tubes are kept the same for all m...

Constant mean curvature (CMC) hypersurfaces in a compact Riemannian manifold (Mm+1, g) constitute an important class of submanifolds and have been studied extensively. In this paper we are interested in degenerating families of such submanifolds which ‘condense’ to a submanifold Kk ⊂ Mm+1 of codimension greater than 1. It is not hard to see that the closer a CMC hypersurface is (e.g. in the Hau...

Computational fluid dynamics (CFD) is a popular tool in the water industry for assessing ultraviolet (UV) reactor performance. However, due to the size of open-channel-type UV reactor systems, the CFD model requires significant computational time. Thus, most evaluations have been conducted using very simplified models. In order to ensure the reliability of this simplified CFD model, precise num...

Transport phenomena in a proton exchange membrane fuel cell (PEMFC) are highly coupled and complicated by multi-phase flow in the several porous components, electrochemical reaction and the three-dimensional geometry. Naturally, therefore, theoretical work is largely manifested in computational fluid dynamics (CFD). However, the comprehensive three-dimensional (3D) CFD method is often prohibiti...

Obtaining reliable CFD predictions of the bronchial flow that reflects the actual flow within a living lung requires the development of a deforming airways model, and the imposition of physiological subject-specific boundary conditions. This thesis addresses these two issues by the development of dynamic CFD models of the bronchial airways using a dynamic CT data set covering the breathing cycl...

This paper presents the CFD modeling methodology and validation for steady-state, normal operation in a PWR fuel assembly. This work is part of a program that is developing a CFD methodology for modeling and predicting single-phase and two-phase flow conditions downstream of structural grids that have mixing devices. The purpose of the mixing devices (mixing vanes in this case) is to increase t...

The primary objective of this study is to evaluate the accuracy of using computational fluid dynamics (CFD) turbulence models to predict entropy generation rates in bypass transitional boundary layers flows under zero and adverse pressure gradients. Entropy generation rates in such flows are evaluated employing the commercial CFD software, ANSYS FLUENT. Various turbulence and transitional model...

Conventional fire and smoke control systems use pressure differences across small openings and cracks in physical barriers as a means to restrict smoke propagation from one space to another and water-spray curtains to diminish or eliminate fire and smoke. Most fire codes of Unite State of American depend upon the National Fire Protection Association (NFPA), guidebooks [1,2]. In turn these propo...

Computational Fluid Dynamics (CFD) has become a useful tool for the study of indoor and outdoor environment problems. Recently, the Massachusetts Institute of Technology (MIT) has developed several Reynolds Averaged Navier-Stokes (RANS) equation models and Large Eddy Simulation (LES) models to enhance the capabilities of CFD for use in indoor and outdoor environment design. The new models have ...