A mathematically defined Wigley hull form is used to investigate the application of a commercial CFD code in prediction of the total resistance and its components from tangential and normal forces on the hull wetted surface. The computed resistance and wave profiles alongside the hull were compared with experimental observations for six different Froude numbers to validate the simulations. The ...

Background: Various variance reduction techniques such as forced detection (FD) have been implemented in Monte Carlo (MC) simulation of nuclear medicine in an effort to decrease the simulation time while keeping accuracy. However most of these techniques still result in very long MC simulation times for being implemented into routine use. Materials and Methods: Convolution-based force...

Computational Fluid Dynamics (CFD) simulations provide a variety of data mining challenges and present an opportunity for novel solutions. A core challenge is that CFD computations can require weeks of computation on expensive high performance clusters, delaying investigation of results until a fully converged solution is obtained. 21st Century Systems, Inc. and Brigham Young University have be...

This paper introduces computational fluid dynamics (CFD), a numerical approach widely and successfully used in aerospace engineering, to deal with surface traffic flow related problems. After a brief introduction of the physical and mathematical foundations of CFD, this paper develops CFD implementation methodology for modeling traffic problems such as queue/platoon distribution, shockwave prop...

Due to recent improvements on combustion modeling, three-dimensional Computational Fluid Dynamics (CFD) tools have become essential in aiding in the engine development. They allow the understanding of basic combustion phenomena and help to optimize various parameters of a pre-existing combustion system or to design a combustion chamber from scratch. Combustion systems become more and more compl...

Three-dimensional computational fluid dynamics (CFD) modeling of the gasification performance in a one-stage, entrained-bed coal gasifier (Shell Coal Gasification Process (SCGP) gasifier) was performed, for the first time. The parametric study used various O2/coal and steam/coal ratios, and the modeling used a commercial code, ANSYS FLUENT. CFD modeling was conducted by solving the steady-state...

Three examples of response surface modeling with CFD are presented for combined cycle propulsion components. The examples include a mixed-compression-inlet during hypersonic flight, a hydrogen-fueled scramjet combustor during hypersonic flight, and a ducted-rocket nozzle during all-rocket flight. Three different experimental strategies were examined, including full factorial, fractionated centr...

The intent of this study is to evaluate existing gaps in computational fluid dynamics (CFD) technology with an emphasis on hypersonic flow modeling. The importance of validation is highlighted, especially with respect to the dearth of available hypersonic flow data. Modeling challenges relevant to hypersonic air-breathing propulsion, such as multi-phase flow and turbulent mixing, are discussed ...

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...

This paper focuses on the implementation, validation and exploitation of a vertical dropshaft flow operation using the commercial VOF-based Computational Fluid Dynamics (CFD) code, FLOW-3D ® . Using the experimental data of Chanson (2002), the package was used to simulate the flow patterns in a rectangular dropshaft with plunge-flow pattern. Both k−ε and k−ε RNG turbulence closures were tested ...