The combustion processes and emission formation in pre and main chambers of a Lister 8.1 IDI diesel are simulated with the Computational Fluid Dynamics (CFD) code. The model includes spray atomization, mixture formation and distribution and subsequently the combustion processes and emissions formation modeling are carried out with considering of flow configurations in two chambers. A part load ...

this paper reports a cfd modeling study to investigate the hydrogen-air mixture combustion in a micro scale chamber. nine species with nineteen reversible reactions were considered in the premixed combustion model. the effect of operational and geometrical conditions including; combustor size, wall conductivity, reactant flow rates and hydrogen feed splitting on combustion stability and outlet ...

This paper discusses the development of a computational approach for accurately determining static and dynamic stability and control characteristics of USAF high-performance fighter aircraft. A graduated approach is used to incrementally add Computational Fluid Dynamics (CFD) simulation capability using DoD HPC resources. Static simulations, prescribed motion flight test maneuvers, and System I...

In ventilated tunnel fires, smoke and hot combustion products may form a layer near the ceiling and flow in the direction opposite to the ventilation stream. The existence of this reverse stratified flow has an important bearing on fire fighting and evacuation of underground mine roadways, tunnels and building corridors. In the present study, conducted by the National Institute for Occupational...

Computational fluid dynamics (CFD) of complex processes and complicated geometries embraces the transport of momentum, heat, and mass including the description of reaction kinetics and thermodynamics. The paper outlines the numerical models available for analyzing these processes and presents examples of such methodology. The unprecedented growth in computer capability has resulted in efficient...

This paper describes the application of a new and unconventional numerical method for computational modeling of fluidic micro-handling processes. The key requirement for modeling such processes is the ability to simulate flows with large number of complex shaped moving objects. Conventional body-conformal computational fluid dynamic (CFD) methods are not well suited for simulating such flows an...

Developing virtual performanceand reliability predictive techniques has become essential for the development of (micro)electronic systems. This paper provides an overview of current predictive methodologies, challenges and requirements for the modeling of microelectronics thermal behavior. Critical modeling issues are discussed, from optimizing Integrated Circuit (IC) packaging thermal performa...

A study is currently underway to better understand and influence the maneuvering characteristics of autonomous underwater vehicles (AUVs). A two-pronged approach, using traditional quasi-steady state-space modeling as well as maneuvering experiments performed in unsteady Reynolds-averaged Navier-Stokes simulations (URANS), has been adopted to provide the greatest possible insight into vehicle m...

Computational fluid dynamics (CFD) is a widely used numerical method for simulating complex systems, with applications ranging from aerodynamic science to hydrology. The latticeBoltzmann method is a relatively recent technique that has been shown to be as accurate as traditional CFD methods, but with the ability to integrate arbitrarily complex geometries at a reduced computational cost. Althou...

Classification algorithms often handle large amounts of labeled data. When a label is the result of a very expensive computer experiment (in terms of computational time), sequential selection of samples can be used to limit the overall cost of acquiring the labeled data. This paper outlines the concept of sequential design for classification, and the extension of an existing stateof-the-art res...