Seminar - Development of Advanced Flow Diagnostic Techniques to Study Complex Thermal/Fluid Phenomena by Professor Hui Hu
日期：2017 年 12 月 05 日 ( 星期二)
Time：4:00 pm – 5:00 pm
The talk will start with the description of the recent progress made by the speaker in developing a novel molecule-based flow diagnostic technique, named as Molecular Tagging Velocimetry and Thermometry (MTV&T), for simultaneous measurements of flow velocity and temperature distributions in fluid flows. Unlike most commonly-used particle-based flow diagnostic techniques such as Particle Image Velocimetry (PIV), MTV&T utilizes specially-designed phosphorescent molecules, which can be turned into long-lasting glowing marks upon excitation by photons of appropriate wavelength, as the tracers for both flow velocity and temperature measurements. The unique glamour of the MTV&T technique will be demonstrated from the application examples to study the thermal effects on the wake instabilities behind a heated cylinder, achieve simultaneous velocity and temperature measurements inside micro-channels to investigate unsteady joule heating of electro-osmotic flows (EOF); to quantify the unsteady heat transfer and phase changing process within micro-sized icing water droplets, and to visualize the transient surface water transport processes pertinent to aircraft icing and de-/anti-icing applications.
The second part of the talk will introduce the speaker’s recent research on wind turbine aeromechanics and wake interferences in onshore and offshore wind farms. The experimental studies are conducted in a large-scale Aerodynamic/Atmospheric Boundary Layer (AABL) Wind available at Iowa State University. An array of scaled wind turbine models are placed in atmospheric boundary layer winds with different mean and turbulence characteristics to simulate the situations in onshore and offshore wind farms. In addition to measuring dynamic wind loads (both forces and moments) and the power outputs of the model turbines, a high-resolution Stereo Particle Image Velocity system is used to conduct detailed flow field measurements to quantify the characteristics of the turbulent wake vortex flows and the wake interferences among the wind turbines. The detailed flow field measurements are correlated with the dynamic wind loads and power output measurements to elucidate underlying physics for higher total power yield and better durability of the wind turbines in atmospheric boundary layer (ABL) winds.
Prof. Hui Hu is the Martin C. Jischke Professor of Aerospace Engineering at Iowa State University. He received his BS and MS degrees in Aerospace Engineering from Beijing University of Aeronautics and Astronautics (BUAA) in China, and a PhD degree in Mechanical Engineering from the University of Tokyo in Japan. Dr. Hu is an ASME Fellow and AIAA Associate Fellow. His recent research interests include advanced flow diagnostics, aircraft icing physics and anti-/de-icing technology; film cooling and thermal management of gas turbines; wind turbine aeromechanic and rotorcraft aerodynamics; bio-inspired designs of unmanned-aerial-systems (UAS). Dr. Hu received several prestigious awards in recent years, including 2006 NSF-CAREER Award, 2007 Best Paper in Fluid Mechanics Award (Measurement Science and Technology, IOP Publishing), 2009 AIAA Best Paper Award in Applied Aerodynamics, 2012 Mid-Career Achievement in Research Award of Iowa State University, 2013 AIAA Best Paper Award in Ground Testing Technology, and 2014 Renewable Energy Impact Award of Iowa Energy Center. Further information about Dr. Hu’s technical background and recent research activities is available at: http://www.aere.iastate.edu/~huhui/.