Ryan Patterson Email & Phone Number

Lake Forest, California, United States

Thesis Title: “Active Flow Control for Rotorcraft Vibration Reduction”Advisor: Prof. Peretz Friedmann, University of MichiganObjective: Development of a computational framework for simulating the effects of active flow control on helicopter rotor blade vibrations.Accomplishments:• Collaborated with researchers from Georgia Tech to assess changes in aerodynamic loads due to several fluidic actuator configurations using 2D/3D CFD simulations and wind tunnel experiments.• Developed a reduced-order model (ROM) for predicting unsteady lift, drag, and pitching moment due to fluidic actuation. The ROM is based on training data obtained from CFD simulations. The ROM mimics direct CFD results and has significantly faster computer run time.• Applied broadband identification signals in CFD simulations to efficiently generate ROM training data. Frequency sweeps, as well as other signals common for system identification, were explored. The fluidic actuators have discrete on-off modes; thus, discrete pseudorandom signals are needed.• Incorporated the aerodynamic ROM into an aeroelastic rotor simulation code, developed at UM, to perform open-loop and closed-loop control simulations aimed at vibratory load reduction.• Demonstrated that significant reduction of vibrations is possible, up to 83% below the baseline. This is comparable to the vibration reduction obtained with a mechanically operated microflap.• Examined the trade-off between vibration reduction and rotor performance penalty.

Developed an aeroelastic simulation to assess the potential for wind-excited instabilities of ground-mounted photovoltaic solar tracker arrays, i.e., “solar farms.”

GSI for AE 325 (Aerodynamics), UM Dept of Aerospace Engineering

Doctor Of Philosophy - Phd, Aerospace Engineering

Master Of Science (Ms), Aerospace Engineering

Activities and Societies: AIAA, American Helicopter Society (AHS)

Bachelor Of Science (Bs), Aerospace Engineering

Activities and Societies: Sigma Gamma Tau, Michigan Running Club (MRun)