Seminar: Dhuree Seth
All dates for this event occur in the past.
Seminar Speaker
Dhuree Seth
Embry-Riddle Aeronautical University
Seminar Title
Contributions to the Understanding of Ship Airwakes Using Advanced Flow Diagnostic Techniques
Seminar Location
Online only via Zoom: go.osu.edu/ARCseminar
Abstract
The objective of Seth's research was to better characterize the complex, three-dimensional, unsteady aerodynamic flows produced by the superstructures of ships, i.e., the airwake. This problem is relevant and important because the turbulent airwake significantly and adversely affects the ability for aircraft to operate safely from the decks of Navy ships. To this end, a series of wind tunnel measurements were performed in ERAU LSWT on the SFS2 simplified frigate shape, which has a flight deck at its stern. The measurements were performed with and without a simulated atmospheric boundary (ABL), which included scaling of its thickness, velocity profile, and turbulence. The ABL was simulated using Cowdrey grid method, which comprises sets of horizontal rods in the wind tunnel upstream of the test section. Two wind tunnels were used, in part to cover a wind range of Reynolds numbers based on ship length in the range of 0.6–7.7 million. The measurements were performed using a combination of hot-wire anemometry, particle image velocimetry (PIV) and especially time-resolved PIV measurements in various streamwise and crosswise planes. The experiments was also supported by surface oil flow visualization, which was used to interpret the quantitative measurements. The results suggested the existence of asymmetric, intermittent flow in the near-wall regions of the deck, and bi-stable fluctuations in the recirculation region behind the hangar and behind the stern of the ship. The measurements also showed the development of shear layers at the corners of the flight deck on both the port and starboard sides, and sets of counterrotating vortices at the edges of the flight deck. Further, reduced order modeling analysis such as Proper Orthogonal Decomposition and Spectral Proper-Orthogonal Decomposition was used to extract the dominant energy modes from the TR-PIV measurements to better quantify the complex three-dimensional, spatially turbulent structures exhibited in the airwake.
About the Speaker
Dhuree Seth is a Ph.D. candidate at Embry-Riddle Aeronautical University (ERAU) and is graduating August 2020. She is working with Dr. J. Gordon Leishman on the experimental task of investigating the ship airwakes and many challenges faced by aircraft making at-sea landings. Her research interest lies in unsteady aerodynamics, wind tunnel and water tunnel testing, rotorcraft aerodynamics, and wingtip vortex. After studying computer science and engineering as an undergraduate, she earned a Masters of Science in aerospace engineering at the University of Dayton. She has worked as a graduate teaching assistant for Experimental Aerodynamics lab class and as an instructor for Introduction to Aerospace Vehicles course. Currently, she is working as a graduate research assistant at the ERAU low-speed wind tunnel, where she assists in designing and setting up experiments, executing data analysis, and running undergraduate labs. She has active participation in organizations such as American Institute of Aeronautics and Astronautics (AIAA) and Society of Women Engineers (SWE). She served in various positions with the AIAA Cape Canaveral section council and recently served as a member of the Liaison Host committee for SWE WE Local Tampa 2019.
Hosted by Dr. Jim Gregory, Professor and Chair of the Department of Mechanical and Aerospace Engineering, and Dr. Matt McCrink, Research Scientist.