07-12-2019 | SeungJoon Yang: 117th NIA CFD Seminar: Drag and Noise Reduction of Flatback Trailing-edge Airfoils by Span-wise Wavy Trailing-edge Design
Title: 117th NIA CFD Seminar: Drag and Noise Reduction of Flatback Trailing-edge Airfoils by Span-wise Wavy Trailing-edge Design
Speaker: Dr. SeungJoon Yang
Date: Friday, July 12, 2019
Location: NIA, Room 137
Abstract: The flatback airfoil is a promising idea for future large wind turbine blade structure design; however, it causes notable drag increase and low frequency tonal noise due to the presence of span-wise coherent standing flow and Karman vortex shedding at the trailing edge. Current research proposes a span-wise wavy trailing edge design as a solution to the flatback airfoil drag and noise, and provides relevant CFD results. Proposed span-wise wavy trailing edge prevents the span-wise coherent standing flow and vortex shedding, results in a decrease of the tonal noise and pressure drag of the airfoil. A design parametric study for the span-wise wavy trailing edge is conducted, and followed by the isolated rotor simulation of the SNL100-meter blade. In the parametric study, the best aerodynamic span-wise wavy trailing edge design increases maximum 150% of lift/drag ratio, and reduces the tonal noise by 20-25dB(SPL), compared to the flatback airfoil. In the SNL100-meter rotor blade simulation, the span-wise wavy trailing edge results in 2.62% of turbine power generation, and 5-15dB(SPL) of tonal noise reduction. In the research, Delayed Detached Eddy Simulation is employed in HPC environment. In-house(at University of Maryland) developed N-S solvers, OVERTURNS(CPU-based) and GPURANS3D(GPGPU-based) are used for the computation.
Bio: SeungJoon Yang is a recent granted (May 2019) PhD from University of Maryland. He had granted his B.S. and M.S. degree at the Korea Aerospace University, Goyang, South Korea. He is born and raised in South Korea, came and joined the CFD research group in the Alfred Gessow Rotor Craft Center at University of Maryland in 2013, after graduating from Korea Aerospace University. During his M.S program, his research mostly focused on the fuel injection/mixing system for the high-speed propulsion such as Gas-Turbine/Ramjet/Scramjet, approaching with CFD techniques, such as Multi-phase flow simulation(Liquid-Gas / Solid-Liquid-Gas), Large Eddy Simulation, Particle Tracking Simulation. At the University of Maryland, he joined the State of Maryland Wind Energy Research program, and focused on drag/noise reduction research for the future large wind turbine blade. His recent research is interested in turbulent modeling, blunt body aerodynamics, aero-acoustics, and GPU computation.