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Mechanical Engineering Commons

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Full-Text Articles in Mechanical Engineering

Investigation Of Reynolds Stresses In A 3d Idealized Urban Area Using Large Eddy Simulation, Akshay A. Gowardhan, E. R. Pardyjak, Inanc Senocak, M. J. Brown Sep 2007

Investigation Of Reynolds Stresses In A 3d Idealized Urban Area Using Large Eddy Simulation, Akshay A. Gowardhan, E. R. Pardyjak, Inanc Senocak, M. J. Brown

Mechanical and Biomedical Engineering Faculty Publications and Presentations

High resolution, large eddy simulation (LES) of neutral flow through an array of cubes has been conducted with periodic boundary conditions in lateral and longitudinal directions. In this paper, we first describe the model formulation and validate the simulation by comparing the mean flow and turbulence statistics with wind-tunnel experimental data from a cube array of buildings. The LES model is then used to investigate the physical mechanisms that lead to the low turbulent stresses that have been reported in the lower half of the urban canopy layer. To do this, the urban boundary layer is conceptually broken down into …


Lower Extremity Mechanics During Cutting Tasks In Different Shoe-Turf Combinations, Rafael Garcilazo Apr 2007

Lower Extremity Mechanics During Cutting Tasks In Different Shoe-Turf Combinations, Rafael Garcilazo

McNair Scholars Research Journal

The demands placed on the lower extremity when performing jumping and cutting maneuvers are depending, in part, on the interaction between the playing surface and the athlete's footwear. Higher demands are likely to result in increased incidence of injury, so for safety reasons it is important to quantify how the shoe-turf interface affects joint loads. The purpose of this study is to compare the forces on the lower extremity while landing and side cutting (rapid direction change at approximately 45 degrees) on artificial football turf with different styles of football cleats.


Conditions For Capacitor Voltage Regulation In A Five-Level Cascade Multilevel Inverter: Application To Voltage-Boost In A Pm Drive, John Chiasson, Burak Ozpineci, Zhong Du, Leon M. Tolbert Jan 2007

Conditions For Capacitor Voltage Regulation In A Five-Level Cascade Multilevel Inverter: Application To Voltage-Boost In A Pm Drive, John Chiasson, Burak Ozpineci, Zhong Du, Leon M. Tolbert

Electrical and Computer Engineering Faculty Publications and Presentations

A cascade multilevel inverter is a power electronic device built to synthesize a desired AC voltage from several levels of DC voltages. Such inverters have been the subject of research in the last several years, where the DC levels were considered to be identical in that all of them were either batteries, solar cells, etc. Similar to previous results in the literature, the work here shows how a cascade multilevel inverter can be used to obtain a voltage boost at higher speeds for a three-phase PM drive using only a single DC voltage source. The input of a standard three-leg …


A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using A Single Dc Source For A Pm Synchronous Motor Drive, John N. Chiasson, Burak Ozpineci, Leon M. Tolbert Jan 2007

A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using A Single Dc Source For A Pm Synchronous Motor Drive, John N. Chiasson, Burak Ozpineci, Leon M. Tolbert

Electrical and Computer Engineering Faculty Publications and Presentations

The interest here is in using a single DC power source to construct a 3-phase 5-level cascade multilevel inverter to be used as a drive for a PM traction motor. The 5-level inverter consists of a standard 3-leg inverter (one leg for each phase) and an H-bridge in series with each inverter leg, which use a capacitor as a DC source. It is shown that one can simultaneously maintain the regulation of the capacitor voltage while achieving an output voltage waveform which is 25% higher than that obtained using a standard 3-leg inverter by itself.