Aerospace Engineering Commons^™

Analysis Of Wake Vortices Of A Medium Range Twin-Propeller Military Cargo Aircraft Using Statistically Designed Experiments, Burhan Sahin

Mechanical & Aerospace Engineering Theses & Dissertations

An experimental study was initiated to analyze the trajectories of the streamwise vortices behind the wing tip and flap of a medium range and propeller driven twin-engine military cargo aircraft. The model used for the experimental study was a generic, high wing and half model of a propeller driven aircraft and mounted within Old Dominion University's Low Speed Wind Tunnel where the wind tunnel flow speed was set to constant value of 9 m/sec. The main purpose of the study was to reach regression models for the motion and vorticity strength of both vortices under varying factors such as angle …

Overnight Atmospheric Transport And Chemical Processing Of Photochemically Aged Houston Urban And Petrochemical Industrial Plume, Rahul A. Zaveri, Paul B. Voss, Carl M. Berkowitz, Edward Fortner, Jun Zheng, Renyi Zhang, Ralph J. Valente, Roger L. Tanner, Daniel Holcomb, Thomas P. Hartley, Leslie Baran

Engineering: Faculty Publications

Overnight atmospheric transport and chemical evolution of photochemically aged Houston urban and petrochemical industrial plume were investigated in July 2005. We report here on the 26 July episode in which the aged plume was tagged 1.5 h before sunset with a pair of free-floating controlled meteorological balloons, which guided quasi-Lagrangian aircraft sampling in the plume as it was advected 300 km to the north over 8 h. The aged plume around sunset was well mixed within a 1600 m residual layer, and was characterized by enhanced levels of aerosol, O3, CO, olefins, acetaldehyde, total odd nitrogen compounds (NOy), and relatively …

Chemical Evolution Of Volatile Organic Compounds In The Outflow Of The Mexico City Metropolitan Area, E. C. Apel, L. K. Emmons, T. Karl, F. Flocke, A. J. Hills, S. Madronich, J. Lee-Taylor, A. Fried, P. Weibring, J. Walega, D. Richter, X. Tie, L. Mauldin, T. Campos, A. Weinheimer, D. Knapp, B. Sive, L. Kleinman, S. Springston, R. Zaveri, J. Ortega, Paul Voss, D. Blake, A. Baker, C. Warneke, D. Welsh-Bon, J. De Gouw, J. Zheng, R. Zhang, J. Rudolph, W. Junkermann, D. D. Riemer

Engineering: Faculty Publications

The volatile organic compound (VOC) distribution in the Mexico City Metropolitan Area (MCMA) and its evolution as it is uplifted and transported out of the MCMA basin was studied during the 2006 MILAGRO/MIRAGE-Mex field campaign. The results show that in the morning hours in the city center, the VOC distribution is dominated by non-methane hydrocarbons (NMHCs) but with a substantial contribution from oxygenated volatile organic compounds (OVOCs), predominantly from primary emissions. Alkanes account for a large part of the NMHC distribution in terms of mixing ratios. In terms of reactivity, NMHCs also dominate overall, especially in the morning hours. However, …

Laminar-Turbulent Transition For Attached And Separated Flow, Qian Zhang

University of Kentucky Doctoral Dissertations

A major challenge in the design of turbomachinery components for aircraft gas turbine engines is high cycle fatigue failures due to flutter. Of particular concern is the subsonic/transonic stall flutter boundary which occurs at part speed near the stall line. At these operating conditions the incidence angle is large and the relative Mach number is high subsonic or transonic. Viscous effects dominate for high incidence angles.

In order to predict the flutter phenomena, accurate calculation of the steady and unsteady aerodynamic loading on the turbomachinery airfoils is necessary. The development of unsteady aerodynamic models to predict the unsteady forces and …