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Designing A Green Aircraft: Cal Poly's 2009 Undergraduate Aircraft Designs, Robert A. McDonald, Bruce Wright 2010 California Polytechnic State University, San Luis Obispo

Designing A Green Aircraft: Cal Poly's 2009 Undergraduate Aircraft Designs, Robert A. Mcdonald, Bruce Wright

Aerospace Engineering

The Cal Poly senior design class submitted six designs this year in response to the 2009 Undergraduate Team Aircraft Design Competition. This paper summarizes our experiences teaching design through this RFP and brings the student's insights together.


Lift Superposition And Aerodynamic Twist Optimization For Achieving Desired Lift Distributions, Kevin A. Lane, David D. Marshall, Robert A. McDonald 2010 California Polytechnic State University - San Luis Obispo

Lift Superposition And Aerodynamic Twist Optimization For Achieving Desired Lift Distributions, Kevin A. Lane, David D. Marshall, Robert A. Mcdonald

Aerospace Engineering

A method for achieving an arbitrary lift distribution with an arbitrary planform is presented. This is accomplished through optimizing aerodynamic twist for a given number of either known airfoils or airfoils to be designed. The spanwise locations of these airfoils are optimized to get as close to the desired lift distribution as possible. Airfoils are linearly interpolated between these points. After aerodynamic twist, the planform is twisted geometrically using radial basis functions to model the twist distribution. The aerodynamic influence of each twist distribution is determined and all are superimposed to determine the function weights of each twist function, yielding …


A Three Dimensional Vortex Particle-Panel Method For Modeling Propulsion-Airframe Interaction, Jacob S. Calabretta, Robert A. McDonald 2010 California Polytechnic State University - San Luis Obispo

A Three Dimensional Vortex Particle-Panel Method For Modeling Propulsion-Airframe Interaction, Jacob S. Calabretta, Robert A. Mcdonald

Aerospace Engineering

The panel code has been a pivotal tool for aerodynamic simulations for decades, today providing users with quick solutions without the necessity of a volume grid. Unfortunately, the panel code also carries with it some inherent shortcomings when compared with other methods. One such weakness is its inability to account for any work done on or by the system in question. This paper proposes a method to address this issue by combining vortex particles with a panel code, and using them to model the work effects of a propeller or engine. While the proposed model is still a work in …


Towards Efficient Viscous Modeling Based On Cartesian Methods For Automated Flow Simulation, Patrick Hu, Hongwu Zhao, Ramji Kamakoti, Nagendra Dittakavi, Liping Xue, Kan Ni, Shaolin Mao, David D. Marshall, Michael Aftosmis 2010 Advanced Dynamics Inc.

Towards Efficient Viscous Modeling Based On Cartesian Methods For Automated Flow Simulation, Patrick Hu, Hongwu Zhao, Ramji Kamakoti, Nagendra Dittakavi, Liping Xue, Kan Ni, Shaolin Mao, David D. Marshall, Michael Aftosmis

Aerospace Engineering

The advanced Computational Fluid Dynamics (CFD) techniques that address the current limitations of Cartesian-based Navier-Stokes CFD schemes are explored in current investigation. Three promising methods of implementing improved wall boundary conditions are applied: (1) the enhanced diamond path stencil approach, (2) the reformulated extended extrapolation boundary condition, and (3) the ghost cell method. Several initial testing cases have been conducted with all these three boundary conditions, including the flow past a circular cylinder, flow past a flat plate at different inclined angles and flow past an AGARD RAE2822 airfoil. All the results show the effectiveness of these boundary conditions in …


Lift Superposition And Aerodynamic Twist Optimization For Achieving Desired Lift Distributions, Kevin A. Lane, David D. Marshall, Robert A. McDonald 2010 California Polytechnic State University - San Luis Obispo

Lift Superposition And Aerodynamic Twist Optimization For Achieving Desired Lift Distributions, Kevin A. Lane, David D. Marshall, Robert A. Mcdonald

Robert A. McDonald

A method for achieving an arbitrary lift distribution with an arbitrary planform is presented. This is accomplished through optimizing aerodynamic twist for a given number of either known airfoils or airfoils to be designed. The spanwise locations of these airfoils are optimized to get as close to the desired lift distribution as possible. Airfoils are linearly interpolated between these points. After aerodynamic twist, the planform is twisted geometrically using radial basis functions to model the twist distribution. The aerodynamic influence of each twist distribution is determined and all are superimposed to determine the function weights of each twist function, yielding …


Conceptual Design Of A Next Generation, 150 Passenger Commercial Transport, Ryan Halper, Kevin Lane, Dustin Marschik, Brett Morham, John Pham, Robert A. McDonald, Bruce Wright 2010 California Polytechnic State University, San Luis Obispo

Conceptual Design Of A Next Generation, 150 Passenger Commercial Transport, Ryan Halper, Kevin Lane, Dustin Marschik, Brett Morham, John Pham, Robert A. Mcdonald, Bruce Wright

Robert A. McDonald

In response to the 2008-2009 AIAA Undergraduate Team Design Competition's Request for Proposals for an advanced, environmentally compatible, 150 seat commercial transport; Jackson West has designed the Sparrow JS-3. The Sparrow represents the next step in the evolution of commercial aviation. Scheduled to enter service in 2018, The Sparrow will compete directly with the Boeing 737 and Airbus A320. Its improvements in fuel consumption and operating cost, as well as its reduced environmental impact, make The Sparrow the ideal solution to this RFP.


Conceptual Design Of An Environmentally Responsible 150-Passenger Commercial Aircraft, Natalie R. Smith, Bryan Blessing, James Dixon, Allen Mackey, Gregory McKenzie, Robert A. McDonald, Bruce Wright 2010 California Polytechnic State University - San Luis Obispo

Conceptual Design Of An Environmentally Responsible 150-Passenger Commercial Aircraft, Natalie R. Smith, Bryan Blessing, James Dixon, Allen Mackey, Gregory Mckenzie, Robert A. Mcdonald, Bruce Wright

Robert A. McDonald

Verde is an environmentally responsible commercial transport seating 150 dual-class passengers, designed in response to the 2008-2009 Request for Proposal from the American Institute of Aeronautics and Astronautics Undergraduate Team Aircraft Design Competition. While the airline industry faces increasing pressures from the cost of fuel and the responsibility of environmental impact, the next generation of this aircraft class must operate more efficiently and address those environmental needs. Therefore, all design decisions for Verde focused first on reducing fuel burn, second on reducing emissions, then noise, and finally on maintaining flyaway cost, airport integration, and passenger comfort. The final design utilizes …


A Three Dimensional Vortex Particle-Panel Method For Modeling Propulsion-Airframe Interaction, Jacob S. Calabretta, Robert A. McDonald 2010 California Polytechnic State University, San Luis Obispo

A Three Dimensional Vortex Particle-Panel Method For Modeling Propulsion-Airframe Interaction, Jacob S. Calabretta, Robert A. Mcdonald

Robert A. McDonald

The panel code has been a pivotal tool for aerodynamic simulations for decades, today providing users with quick solutions without the necessity of a volume grid. Unfortunately, the panel code also carries with it some inherent shortcomings when compared with other methods. One such weakness is its inability to account for any work done on or by the system in question. This paper proposes a method to address this issue by combining vortex particles with a panel code, and using them to model the work effects of a propeller or engine. While the proposed model is still a work in …


Parameter Estimation Of Fundamental Technical Aircraft Information Applied To Aircraft Performance, Mike Vallone, Robert A. McDonald 2010 California Polytechnic State University - San Luis Obispo

Parameter Estimation Of Fundamental Technical Aircraft Information Applied To Aircraft Performance, Mike Vallone, Robert A. Mcdonald

Robert A. McDonald

Inverse problems can be applied to aircraft in many areas. One of the disciplines within the aerospace industry with the most openly published data is in the area of aircraft performance. Many aircraft manufacturers publish performance claims, flight manuals and Standard Aircraft Characteristic (SAC) charts without any mention of the more fundamental technical information such as CD0. With accurate tools, generalized aircraft models and a few curve-fitting techniques, it is possible to evaluate vehicle performance and estimate these technical parameters.

With this goal a program has been written in Matlab to calculate the fundamental information behind a …


Designing A Green Aircraft: Cal Poly's 2009 Undergraduate Aircraft Designs, Robert A. McDonald, Bruce Wright 2010 California Polytechnic State University, San Luis Obispo

Designing A Green Aircraft: Cal Poly's 2009 Undergraduate Aircraft Designs, Robert A. Mcdonald, Bruce Wright

Robert A. McDonald

The Cal Poly senior design class submitted six designs this year in response to the 2009 Undergraduate Team Aircraft Design Competition. This paper summarizes our experiences teaching design through this RFP and brings the student's insights together.


Improved Geometry Modeling For High Fidelity Parametric Design, James R. Gloudemans, Robert A. McDonald 2010 California Polytechnic State University, San Luis Obispo

Improved Geometry Modeling For High Fidelity Parametric Design, James R. Gloudemans, Robert A. Mcdonald

Robert A. McDonald

Advanced multidisciplinary physics-based design and analysis capabilities are required to pursue the revolutionary vehicle and technology concepts needed to meet the goals of the aerospace industry for the next 10-30 years. The multidisciplinary physics critical to advancing aerospace technology all have one common bond, the shape, size, and form of the underlying aircraft - its geometry. An aircraft shape is the natural starting point for multidisciplinary analysis and optimization (MDAO). Vehicle Sketch Pad (VSP) is an aircraft geometry tool for rapid evaluation of advanced design concepts which was developed by NASA and is available to industry at large. VSP allows …


Simulations Of Flow Over Wind Turbines, Dnyanesh A. Digraskar 2010 University of Massachusetts Amherst

Simulations Of Flow Over Wind Turbines, Dnyanesh A. Digraskar

Masters Theses 1911 - February 2014

One of the most abundant sources of renewable energy is wind. Today, a considerable amount of resources are being utilized for research on harnessing the wind energy efficiently. Out of all the factors responsible for efficient energy production, the aerodynamics of flow around the wind turbine blades play an important role. This work aims to undertake aerodynamic analysis of a Horizontal Axis Wind Turbine. A steady state, incompressible flow solver for multiple reference frames, MRFSimple- Foam is modified and used for performing simulations of flow over National Renewable Energy Laboratory Phase VI wind turbine rotor. The code is first tested …


Laminar-Turbulent Transition For Attached And Separated Flow, Qian Zhang 2010 University of Kentucky

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 …


Mixi Thruster Tungsten And Thoriated Tungsten Testing, Jesse R. Miller 2010 California Polytechnic State University, San Luis Obispo

Mixi Thruster Tungsten And Thoriated Tungsten Testing, Jesse R. Miller

Aerospace Engineering

The purpose of this project is to build and evaluate a tungsten filament cathode for the 3-cm Miniature Xenon Ion (MiXI) thruster. The filament is to be used for future tests within the CP 3-cm MiXI and thoriated tungsten is to be examined as a possible alternative. No testing of these filaments was conducted, but the preparatory work has been conducted for future testing.


Numerical Investigation Of Aeroelastic Mode Distribution For Aircraft Wing Model In Subsonic Air Flow, Marianna A. Shubov, Stephen B. Wineberg, Robert Holt 2010 University of New Hampshire

Numerical Investigation Of Aeroelastic Mode Distribution For Aircraft Wing Model In Subsonic Air Flow, Marianna A. Shubov, Stephen B. Wineberg, Robert Holt

Mathematics & Statistics

In this paper, the numerical results on two problems originated in aircraft wing modeling have been presented. The first problem is concerned with the approximation to the set of the aeroelastic modes, which are the eigenvalues of a certain boundary-value problem. The affirmative answer is given to the following question: can the leading asymptotical terms in the analytical formulas be used as reasonably accurate description of the aeroelastic modes? The positive answer means that these leading terms can be used by engineers for practical calculations. The second problem is concerned with the flutter phenomena in aircraft wings in a subsonic, …


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 2010 Pacific Northwest National Laboratory

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 …


Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha Ph.D., Florin Bobaru Ph.D. 2010 University of Nebraska at Lincoln

Studies Of Dynamic Crack Propagation And Crack Branching With Peridynamics, Youn Doh Ha Ph.D., Florin Bobaru Ph.D.

Department of Engineering Mechanics: Faculty Publications

In this paper we discuss the peridynamic analysis of dynamic crack branching in brittle materials and show results of convergence studies under uniform grid refinement (m-convergence) and under decreasing the peridynamic horizon (δ-convergence). Comparisons with experimentally obtained values are made for the crack-tip propagation speed with three different peridynamic horizons.We also analyze the influence of the particular shape of themicro-modulus function and of different materials (Duran 50 glass and soda-lime glass) on the crack propagation behavior. We show that the peridynamic solution for this problem captures all the main features, observed experimentally, of dynamic crack propagation and branching, as well …


Pilot Source Study: An Analysis Of Pilot Backgrounds And Subsequent Success In Us Regional Airline Training Programs, Guy M. Smith, David A. NewMyer, Elizabeth Bjerke, Mary Niemczyk, Raymond A. Hamilton 2010 Embry Riddle Aeronautical University

Pilot Source Study: An Analysis Of Pilot Backgrounds And Subsequent Success In Us Regional Airline Training Programs, Guy M. Smith, David A. Newmyer, Elizabeth Bjerke, Mary Niemczyk, Raymond A. Hamilton

Applied Aviation Sciences - Daytona Beach

The 2010 Pilot Source Study, commissioned to research the success of pilots in initial training for Part 121 operations, analyzed the training performance of 2,156 new-hire pilots in the years 2005-2009. Six regional airlines provided data that was mined from human resource and pilot training files. Five university researchers independently analyzed the data and integrated their results. The study expressed success in terms of fewer extra training events and fewer non-completions in regional airline training. Statistically, the best performing pilots were those who had flight instructor certificates, graduated from collegiate accredited flight programs, received advanced (post-Private) pilot training in college, …


Multiscale Transformation Field Analysis Of Progressive Damage In Fibrous Laminates, Yehia Bahei-El-Din, Ritesh Khire, Prabhat Hajela 2010 The British University in Egypt

Multiscale Transformation Field Analysis Of Progressive Damage In Fibrous Laminates, Yehia Bahei-El-Din, Ritesh Khire, Prabhat Hajela

Centre for Advanced Materials

As part of an ongoing effort to model uncertainty propagation across multiple scales in fibrous laminates, this paper presents a deterministic transformation field analysis for modeling damage progression under membrane forces and bending moments. In this approach, equivalent eigenstresses are computed in the phases and/or plies such that their respective stress components that satisfy the underlying failure criteria are reduced to zero. Superposition of the solutions found for the undamaged laminate under applied loads and under the eigenstress field provide the entire response. Failure criteria are based on stress averages in the fiber and matrix. Damage mechanisms considered are frictional …


Modified Sandwich Structures For Improved Impact Resistance Of Wind Turbine Blades, Yehia Bahei-El-Din, Mostafa Shazly, I. El-Habbal, Y. Elbahy 2010 The British University in Egypt

Modified Sandwich Structures For Improved Impact Resistance Of Wind Turbine Blades, Yehia Bahei-El-Din, Mostafa Shazly, I. El-Habbal, Y. Elbahy

Centre for Advanced Materials

Wind turbine blades are susceptible to damage due to fatigue as well as impact by flying objects and parts broken off failed blades of nearby wind towers. Localized, permanent compression of the foam core and delamination of the fibrous composite face sheets are typical damage modes and can lead to progressive structural failure. Sandwich structures modified by inclusion of flexible polyurethane (PU) layers within the cross section are examined under both impact and dynamic loads. Finite element models of sandwich structures with conventional and modified designs show that sandwich designs modified with PU interlayes exhibit reduced foam core crushing and …


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