MAE Seminar: Advanced Concepts Design Center and Computational Fluid Dynamics
Boeing Technical Fellow, Boeing
Abstract: In order to familiarize one with various gradient-based optimization techniques, a very simple model problem is introduced. The Spider & Fly geodesic problem is analyzed with Steepest-Descent, Nash, Newton and quasi-Newton methods. An active constraint is then introduced to illustrate how to solve a Dual Lagrange problem, which satisfies the KKT conditions of optimality. These solutions are accompanied with detailed tabulated data of the state at each iteration such that the interested student can verify his/her own implementation of these techniques. The seminar will conclude with a few industrial applications of aerodynamic shape optimization, which illustrate the utility, efficiency and robustness of the current state-of-the-art/practice.
Bio: Vassberg is technical lead and chief aerodynamicist of the BCA Advanced Concepts Design Center in Southern California. He is a Boeing Technical Fellow, an AIAA Fellow, and recipient of the AIAA Aerodynamics Award in 2012 and the International Cooperation Award in 2017. Previously, he was chief aerodynamicist of Boeing’s Research & Technology organization, and as such, he was the principal investigator of the Advanced Joint Air Combat System (AJACS), Speed-Agile Configuration Development (SACD) and Over-Wing Nacelle (OWN) programs. The SACD program received the 2013 Aviation Week Laureate Award in Aero and Propulsion. Vassberg joined Boeing (McDonnell Douglas) in 1982, working in the Aerodynamic Technology Programs group, where he co-developed transonic airfoil technologies such as optimum upper-surface pressure-recovery paths, divergent trailing edge and trailing-edge wedge concepts; he validated these technological advancements with wind-tunnel testing and computational simulations. Since then, he has developed, matured, transitioned and applied numerous computational fluid dynamics (CFD) methods and aerodynamic technologies to aircraft design. In order to accomplish this, he has worked about half of his career in aerodynamic research and technology groups and the other half in aircraft program development organizations. During his 36-year career at Boeing, Vassberg has engaged and collaborated with NASA Ames and Langley Research Centers, the Air Force Research Laboratory and the Naval Research Laboratory, as well as with various academic institutions. He is considered a world authority in the development and application of CFD and aerodynamic shape optimization for aerodynamic design within an aircraft design environment. Vassberg is chairman and a charter member of the International AIAA CFD Drag Prediction Workshop (DPW) organizing committee, designer of the Common Research Model (CRM), co-developer of the Juncture Flow Model (JFM), and is on the Advisory Board for the AIAA High-Lift Prediction Workshop. Aircraft programs that he has worked on or supported include: C-17, KC-10, MD-11, MD-12, MD-XX, MD-80, MD-90, MD-95, UHB, B787 DreamLiner, B747, B777, B737, B767, B717, BWB, LCF DreamLifter, OAW, HSCT and various on-going projects. He holds over 20 patents related to aerodynamic technologies, including six related to the Advanced Winglets of the B737-MAX. He has authored over 100 publications, and is an associate editor for the AIAA Journal of Aircraft. Vassberg has pioneered new fields of numerical simulation including in-flight refueling hose-drogue dynamics, towed-decoy dynamics, fast surface-panel methods and globally-elliptic meshing. Vassberg received his Ph.D. from the University of Southern California in 1992, and his M.S. and B.S. from Texas A&M University in 1981 and 1980, respectively, all in aerospace engineering. He has taught at the University of California, Irvine in the MAE Department and is currently on advisory boards for USC’s Aerospace & Mechanical Engineering Department and Texas A&M’s Aerospace Engineering Department. He is a Distinguished Alumni of TAMU, receiving the Outstanding Aerospace Engineer Award in 2016.