Computational Fluid Dynamics (CFD) Modeling of a Helicopter Slung Load
I used OVERFLOW, a NASA research CFD code utilizing overset grid methodologies, to understand the flow around helicopter slung loads. The CONEX, a common slung load for a helicopter, is subject to strong vortex shedding at high Reynolds number. The forces and moments on the CONEX cause dramatic load swinging and twisting, which changes the flight and handling characteristics of the helicopter and force the pilot to fly much more slowly. I first compared forces, moments, and the time periods of vortex shedding with experimental wind tunnel testing to verify that the CFD code was successfully capturing the physics, then used the CFD simulations to design a passive vertical stabilizer for the CONEX.
The following papers document some of the work I did on this project--at that time my name was still Misty Berry:
Berry, M. "Comparison of CFD Methodologies for High Reynolds Number Flow Over a Square Cylinder." ASME Old Guard competition, 4th place District E winner. 2002.
Berry, Misty D. "Computational Fluid Dynamics Simulations of the Container Express as a Helicopter Slung Load." FEDSM2003-45753 2nd Place Winner for the Student Paper Competition in the 4th ASME/JSME Joint Fluids Engineering Conference. Honolulu, HI. Summer 2003.
Flight and Controls System Modeling for a Martian Aircraft
I modified a NASA flight physics simulation code that contained an adaptive algorithm for flight control in order to simulate the way that a proposed aerial vehicle would behave in the Martian atmosphere. Martian flight will occur at the low Reynolds number and high Mach number regime, which means that shocks are much more likely to form at very small angles of attack. I used CFD data to estimate the stability derivatives for the proposed design, and then modified the code to simulate the Martian flyer and the Martian atmosphere.
K. Krishnakumar, K. Gundy-Burlet, M. Aftosmis, M. Nemec, G. Limes and M. Berry. “Intelligent Control for the BEES Flyer.” AIAA-2004-6274 AIAA 1st Intelligent Systems Technical Conference, Chicago, Illinois, Sep. 20-22, 2004
D. Dasgupta, K. Krishnakumar, D. Wong, and M. Berry. “Immunity-Based Aircraft Fault Detection System.”
AIAA-2004-6277 AIAA 1st Intelligent Systems Technical Conference, Chicago, Illinois, Sep. 20-22,2004
Dynamic Soaring in Oceanic Boundary Layer Gradients
I started at Stanford University in September 2003, and received my Master's degree in Aerospace/Astrospace Engineering in December 2004. I did a quarter of independent research with Professor Ilan Kroo on dynamic soaring. Here is the final paper that I turned in for that research.