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In order to evaluate the performance of jet impingement for high heat-flux cooling, experimental cooling loops based on water and liquid metal jet impingement were designed and constructed. The current liquid metal system, based on an eutectic alloy of gallium and indium (GaIn) with a melting point of 15.7 °C, employs an annular inductive electromagnetic pump. The experiments showed that it is capable of accommodating a heat flux of about 20 MW/m 2 over an area of 10 −4 m 2 . The jet velocity is less than 4 m/s and the required differential pressure from the pump is less than 10 5 Pa. In the...
Jet impingement is a well established cooling methodology used for cooling turbine blades in gas turbine engines. Jet impingement results in high heat transfer coefficients as compared to other conventional modes of single phase heat transfer.Most of the research in jet impingement has been confined to high Reynolds number regime. In order to increase the applicability of this technique to non conventional applications like in a low pressure micro turbine combustors or turbine blades, the behavior of such systems in the low Reynolds number regime should be understood. The present paper is a...
Nuclear vendors and utilities perform numerous simulations and analyses in order to ensure the safe operation of nuclear power plants (NPPs). In general, the simulations are carried out using vendor-specific design codes and best-estimate system analysis codes, most of which were developed based on one-dimensional lumped parameter models. During the past decade, however, computers, parallel computation methods, and three-dimensional computational fluid dynamics (CFD) codes have been dramatically enhanced. The use of advanced commercial CFD codes is considered beneficial in the safety analysis...
This paper reports a computational fluid dynamics (CFD) study on influence of flow field on to gas residence time in boiler furnace. Specifically, investigated was secondary air nozzle direction influence on level of elimination of dead and recirculation zones.As residence time is a ratio between effective furnace volume and gas flow rate from the solid bed,increase of the former through elimination of dead zones would lead to increase of the residence time,and it as a consequence would have an increase of combustion efficiency. Small-scale biomass boilers are specific in a way that their...
Aerodynamics plays an important role in marketing vehicles especially with the recent increases in gas prices. The aerodynamics of one of the widely used vehicle classes (pickup trucks) is examined. The focus is to investigate the effect of the pickup truck configuration on the structure of the airflow around the vehicle and ultimately on the generated aerodynamic drag. The study includes CFD simulations performed using STAR-CCM+ developed by CD-adapco Inc. and full-scale wind tunnel testing conducted in the Langley Full Scale Tunnel (LFST) located at the NASA Langley Research Center but...
Advanced improvements in coupling methods of solid and fluid numerical softwares benefit considerably cardiovascular biomechanics investigations. Deformability of this complicated physiological system plays an important role in biofluid factors such as Wall Shear Stress (WSS). In the current work, taking advantage of recently developed bi-directional interaction tools between Abaqus and STAR-CCM+, a simulation of physiological pulsatile blood flow through aortic arch is implemented. Abaqus solves the computational solid mechanics problem corresponding to the arterial wall while STAR-CCM+ solves...
The capstone airplane design course at the University of Washington, two academic quarters long, has evolved in recent years to cover the airplane design experience from market and needs studies through conceptual design, preliminary design, and detail design, and up to the construction, ground testing, and flight testing of complex research-type small UAVs. Significant engineering resources are devoted to this effort including substantial CAD, CFD-based aerodynamics, NASTRAN-based structural analysis, as well as performance, and stability and control simulations. Wind tunnel tests of...

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