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Full-Text Articles in Engineering
Aerodynamic Analysis Of A Generic Fighter With A Chine Fuselage/Delta Wing Configuration Using Delayed Detached-Eddy Simulation, Tiger L. Jeans, David R. Mcdaniel, Russell M. Cummings, William H. Mason
Aerodynamic Analysis Of A Generic Fighter With A Chine Fuselage/Delta Wing Configuration Using Delayed Detached-Eddy Simulation, Tiger L. Jeans, David R. Mcdaniel, Russell M. Cummings, William H. Mason
Aerospace Engineering
The Modular Transonic Vortex Investigation (MTVI) program at NASA Langley Research Center investigated the transonic characteristics of generic fighter configurations with chined fuselages and delta wings. Previous experiments show that the fuselage and leading edge vortex interactions are detrimental to the vehicle’s aerodynamic characteristics for angles of attack greater than 23º at low angles of sideslip. This is largely due to abrupt asymmetric vortex breakdown, which leads to pronounced pitch-up and significant nonlinearities in lateral stability that could result in roll departure. An improved understanding of the exact origins of this nonlinear behavior would improve future fighter design, and predictive …
An Evaluation Of Proposed Formula 1 Aerodynamic Regulations Changes Using Computational Fluid Dynamics, Robert L. Perry, David D. Marshall
An Evaluation Of Proposed Formula 1 Aerodynamic Regulations Changes Using Computational Fluid Dynamics, Robert L. Perry, David D. Marshall
Aerospace Engineering
This report evaluates the proposed FIA Formula 1 World Championship aerodynamics rules changes intended to increase on track passing for the 2009 season. Two full Formula 1 cars were modeled under close drafting conditions, both under the current regulations and the proposed 2009 regulations to determine whether or not the FIA's goals of reducing down force by 50% and improving sensitivity to leading car wakes would be met. Under the current regulations, a car following another at 2.4 car lengths loses approximately 17% of it down force compared to isolation. The new regulations were counter productive and ineffective, failing both …
An Undergraduate Computational Aerodynamics Curriculum, Keith Bergeron, Russell M. Cummings, Capt Robert Decker, Maj Jacob Freeman, Capt Charlie Hoke, Jurgen Seidel, Scott A. Morton, David M. Mcdaniel
An Undergraduate Computational Aerodynamics Curriculum, Keith Bergeron, Russell M. Cummings, Capt Robert Decker, Maj Jacob Freeman, Capt Charlie Hoke, Jurgen Seidel, Scott A. Morton, David M. Mcdaniel
Aerospace Engineering
Modeling and Simulation (M&S) as part of the Aeronautical Engineering major at the United States Air Force Academy (USAFA) has grown from a one course introduction to an integrated and essential component for developing future aerospace leaders. This paper documents the progress the USAFA Department of Aeronautics (DFAN) has made since 2003 to teach cadets, through a 2-course sequence, how to gain an understanding of aerodynamic phenomena using computational methods made possible with Department of Defense (DoD) High Performance Computing Modernization Program (HPCMP) resources. The first course in of the sequence builds upon demonstrations, made in early core coursework, to …
Numerical Prediction And Wind Tunnel Experiment For A Pitching Unmanned Combat Air Vehicle, Russell M. Cummings, Scott A. Morton, Stefan G. Siegel
Numerical Prediction And Wind Tunnel Experiment For A Pitching Unmanned Combat Air Vehicle, Russell M. Cummings, Scott A. Morton, Stefan G. Siegel
Aerospace Engineering
The low-speed flowfield for a generic unmanned combat air vehicle (UCAV) is investigated both experimentally and numerically. A wind tunnel experiment was conducted with the Boeing 1301 UCAV at a variety of angles of attack up to 70 degrees, both statically and with various frequencies of pitch oscillation (0.5, 1.0, and 2.0 Hz). In addition, pitching was performed about three longitudinal locations on the configuration (the nose, 35% MAC, and the tail). Solutions to the unsteady, laminar, compressible Navier–Stokes equations were obtained on an unstructured mesh to match results from the static and dynamic experiments. The computational results are compared …
Gaussian Process Metamodeling Applied To A Circulation Control Wing, Scott Turner, Tyler Ball, David D. Marshall
Gaussian Process Metamodeling Applied To A Circulation Control Wing, Scott Turner, Tyler Ball, David D. Marshall
Aerospace Engineering
Metamodeling fluid systems is an efficient way to do complex analysis on multivariate problems and can allow for time savings in an optimization setting. Gaussian process metamodels provide a flexibility in modeling that can be extended to both experimental and deterministic experiments. This paper specifically addresses such models applied to computational fluid dynamics analysis of a D circulation control wing. The framework for a generalized approach is first overviewed and then applied to the analysis of the aerodnamics. The Gaussian process regression was essential for both simplifying the calculations required for balanced field length computation and for analysis of complex …
Detached-Eddy Simulation Of The Vortical Flowfield About The Vfe-2 Deltawing, Russell M. Cummings, Andreas Schϋtte
Detached-Eddy Simulation Of The Vortical Flowfield About The Vfe-2 Deltawing, Russell M. Cummings, Andreas Schϋtte
Aerospace Engineering
The numerical simulation of the flow around a 65° delta wing configuration with rounded leading edges is presented. For the numerical simulation the Cobalt Code uses a cell-centered unstructured hybrid mesh approach. Several numerical results are presented for the steady RANS equations as well as for DES and DDES hybrid approaches. The simulations are done as part of the NATO RTO/AVT 113 working group focusing on experimental and numerical research on delta wing configurations with rounded leading edges. Within this paper the focus is related to the dual primary vortex flow topology, especially the sensitivity of the flow to angle …
Introduction Of Software Development Practices Into Aerospace Engineering Curriculum, David D. Marshall, Eric A. Mehiel
Introduction Of Software Development Practices Into Aerospace Engineering Curriculum, David D. Marshall, Eric A. Mehiel
Aerospace Engineering
This paper will discuss the attempts to incorporate software development practices into the aerospace engineering curriculum in order to improve the computer programming capabilities of the students. The main focus is on techniques to integrate functional decomposition, unit level testing, system integration and testing, and verification and validation processes without significantly increasing the workload on the students. The approach taken is an integrated approach where the required information needed for testing and validation are integrated into the course content via in-class examples and homework problems. This same approach was taken for the other software development skills. This has been integrated …
Aerodynamic Performance Enhancement Of A Naca 66-206 Airfoil Using Supersonic Channel Airfoil Design, David Giles, David D. Marshall
Aerodynamic Performance Enhancement Of A Naca 66-206 Airfoil Using Supersonic Channel Airfoil Design, David Giles, David D. Marshall
Aerospace Engineering
Supersonic channel airfoil design techniques have been shown to significantly reduce drag in high-speed flows over diamond shaped airfoils by Ruffin and colleagues. The effect of applying these techniques to a NACA 66-206 airfoil is presented. The design domain entails channel heights of 8-16.6% thickness-to-chord and speeds from Mach 1.5-3.0. Numerical simulations show an increase in the lift-to-drag ratio for airfoils at Mach 2.5 at a 35,000-ft altitude with a 12% channel height geometry showing a benefit of 17.2% at 6-deg angle of attack and a sharp channel leading edge. Wave drag is significantly reduced while viscous forces are slightly …
Short Takeoff Performance Using Circulation Control, Tyler Ball, Scott Turner, David D. Marshall
Short Takeoff Performance Using Circulation Control, Tyler Ball, Scott Turner, David D. Marshall
Aerospace Engineering
Historically, powered lift takeoff analysis has been prohibitively expensive for use in preliminary design. For powered lift, the coupling of aircraft systems invalidates traditional simplistic methods often used in early aircraft sizing. This research creates a tool that will automate the process of takeoff and balanced field length calculations for a circulation control wing aircraft. The process will use high fidelity techniques, such as computational fluid dynamics in order to capture the coupled effects present in circulation control along with Gaussian processes to create a metamodel of that same data to be implemented in a modular takeoff/BFL model. The model …