Conferences, Lectures, & Seminars
Events for September
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AME Seminar
Wed, Sep 01, 2021 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Sutanu Sarkar, University of California at San Diego
Talk Title: Wakes in the Natural Environment
Abstract: Environmental wakes are produced by flows past structures which are engineered (e.g., oceanic submersibles, aerial vehicles, wind turbines, urban structures) or in nature (hills, mountain ranges, islands, seamounts). These wakes impact drag on the incident flow as well as transport of material, pollutants and environmental constituents. We will illustrate wake flow physics with a few examples studied using high-resolution simulation. The wake of a blunt object such as a disk will be contrasted with a streamlined object such as a prolate spheroid with respect to mean velocity, turbulence levels, flow instabilities and coherent structures. We will discuss both a constant density fluid and a density-stratified fluid where buoyancy inevitably alters the wake of the body. We will also present an example from nature, an oceanic current past a submerged hill, where we find synchronization of wake vortices with subharmonics of the oscillating tide and also states of high drag.
Biography: Sutanu Sarkar received his B. Tech. from IIT Bombay, M. S. from Ohio State University and Ph. D. from Cornell University. After 4 years as a staff scientist at ICASE, NASA Langley Research Center, he joined UCSD where he currently holds the Blasker Chair of Environmental Engineering, is a Distinguished Professor in the department of Mechanical & Aerospace Engineering (MAE), and is an affiliate professor at the Scripps Institution of Oceanography. He was Chair of MAE from 2009-2014. He has broad interests in the simulation and modeling of turbulent flows. He has worked in problems concerning the environment, energy, aerospace and propulsion. His current research interests are turbulence and mixing in the ocean and atmosphere, wakes and boundary layers of engineered structures in the natural environment, and renewable energy. He has received a NASA group achievement award (1994), the Bessel Award from the Humboldt Foundation (2001), and was elected Fellow, American Physical Society (2006), Associate Fellow, AIAA (2009) and Fellow, ASME (2010). He is an associate editor of JFM.
Host: AME Department
More Info: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Webcast: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09Location: Seaver Science Library (SSL) - 202
WebCast Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
AME Seminar
Wed, Sep 08, 2021 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Tirtha Banerjee, UC Irvine
Talk Title: TBD
Abstract: The traditional motivation behind studying the dynamics of turbulent wind flow in vegetation canopies has been to understand the nature of mass, momentum and energy exchange between the land surface and the atmosphere. The nature of this interaction determines the microclimate in a forest environment where plants exchange carbon and water and its understanding is relevant for a plethora of applications ranging from ecology, hydrology, agriculture and the modeling of weather and climate. However, the fundamental nature of turbulence in a vegetation canopy is significantly different from the atmospheric surface layer lying above, which means that scaling laws and exchange coefficients from traditional wall bounded flows are not applicable. In a forest canopy, momentum absorption happens not only at the ground surface but throughout the depth of the canopy, resulting in a unique roughness sub layer. Instead of a log-layer, the mean velocity profile is inflected, second order moments are variable with height and skewnesses are large. Large scale coherent structures impart significant impact on the turbulence dynamics. Sweeping motions arising out of downdraft motions of counter-rotating vortices dominate eddy fluxes. A mixing layer model is found to be a better model for describing canopy flows. High frequency measurements and computational fluid dynamics modeling, especially Large Eddy Simulations (LES) has been instrumental in revealing the nature of canopy turbulence in the last few decades. Now this knowledge is being used to push the frontiers of our limited understanding of how wildland fires behave. The main controls on wildland fire behavior -“ fuel (canopy and grasslands), weather and topography are strongly influenced by fine scale physics of canopy turbulence. We will demonstrate that further developments in the understanding of canopy turbulence can benefit wildfire modeling tools and developing actionable management strategies.
Biography: Tirtha Banerjee is an Assistant Professor at the Department of Civil and Environmental Engineering, University of California, Irvine. He received his Bachelor of Science degree in Civil Engineering from Jadavpur University, Calcutta, India in 2011. During his undergraduate studies, he conducted research in the areas of structural dynamics and Aerospace Engineering in India and Germany as a DAAD (German Academic Exchange Service) Fellow. Upon completion of his undergraduate studies in 2011, he moved to the U.S. and joined Duke University in Durham, NC, as a Ph.D. student and conducted theoretical, numerical and experimental studies involving environmental fluid dynamics and turbulent flows. He received his Ph.D. in 2015 and joined the Karlsruhe Institute of Technology (KIT) in Germany for postdoctoral research in atmospheric boundary layer dynamics. He relocated to the U.S. in early 2017 to join the Los Alamos National Laboratory (LANL) in New Mexico and started working on wildfires, ecosystem disturbance as well as wind energy resources. At LANL he received a Chick Keller Postdoctoral Fellowship in 2017 and a Directors Fellowship in 2018. He joined UC Irvine in fall 2019. Research in the Boundary Layers and Turbulence Lab led by Banerjee studies mass, momentum and energy exchange between the land surface and the atmosphere using a range of theoretical, numerical and experimental techniques. He currently serves as an associate editor of the journal Earth Systems and Environment (Springer) and as an editorial board member of the journal Agricultural and Forest Meteorology (Elsevier).
Host: AME Department
More Info: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Webcast: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09Location: Seaver Science Library (SSL) - 202
WebCast Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
AME Seminar
Wed, Sep 15, 2021 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Tim Colonius, Caltech
Talk Title: Simulation of bubbly, cavitating flows with application to shock- and ultrasound-based medical therapies.
Abstract: Models and numerical methods for simulating bubbly, cavitating flows have benefitted from recent advances in sharp and diffuse interface-capturing schemes, but many challenges remain to be solved before they can be routinely used to predict the complex, multiscale flows associated with important applications in engineering and medicine. In particular, the complex phase boundary, small length scales, and fast time scales associated with the dynamics of bubbles and clouds of bubbles strain existing algorithms and computational resources. In this talk, I will review different formulations for multiphase/multicomponent flows that involve large changes in volume, including methods that explicitly resolve the material interface, and ones that model the mixture as either homogeneous, or as a dilute dispersion of spherical bubbles. These methods are demonstrated in applications involving the high-intensity ultrasound and shock waves used for medical imaging and intra- and extra-corporeal manipulation of cells, tissue, and urinary calculi. Such waves are currently used to treat kidney stone disease, plantar fasciitis, and bone nonunion, and they are being investigated as a technique to ablate cancer tumors and mediate drug delivery. In many applications, acoustic waves induce the expansion and collapse of preexisting or newly cavitating bubbles. The resulting bubble dynamics generate large, localized stresses and strains that can be beneficial or deleterious depending on how effectively they can be controlled. I will describe efforts aimed at simulating the collapse of bubbles, both individually and in clusters, in order to characterize these mechanical stresses and strains.
Biography: Tim Colonius is the Frank and Ora Lee Marble Professor of Mechanical Engineering at the California Institute of Technology. He received his B.S. from the University of Michigan in 1987 and M.S and Ph.D. in Mechanical Engineering from Stanford University in 1988 and 1994, respectively. He and his research team use numerical simulations to study a range of problems in fluid dynamics, including aeroacoustics, flow control, instabilities, shock waves, and bubble dynamics. Prof. Colonius also investigates medical applications of ultrasound, and is a member of the Medical Engineering faculty at Caltech. He is a Fellow of the American Physical Society and the Acoustical Society of America, and he is Editor-in-Chief of the journal Theoretical and Computational Fluid Dynamics. He was the recipient of the 2018 AIAA Aeroacoustics Award.
Host: AME Department
More Info: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Webcast: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09Location: Seaver Science Library (SSL) - 202
WebCast Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
AME Seminar
Wed, Sep 22, 2021 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Aaron Brandis, NASA Ames
Talk Title: Dragonfly Titan Entry and Descent System and DrEAM Instrumentation Suite
Abstract: This presentation will discuss the entry and descent phase for the Dragonfly missions arrival at Titan, a moon of Saturn. Dragonfly is a rotorcraft lander mission designed to take advantage of Titan's environment to sample materials and determine surface composition in different geologic settings, and even to search for chemical signatures that could indicate water-based and/or hydrocarbon-based life. The DrEAM instrumentation suite will take measurements of pressure, temperature and heatflux around the aeroshell during the Dragonfly entry.
Biography: Dr Brandis is a senior research scientist employed by AMA Inc in the Aerothermodynamics branch at NASA Ames Research Center. He is the PI for NASA Entry Systems Modeling project, Dragonfly aerothermal lead and PI for Dragonfly Titan entry instrumentation, known as DrEAM. His research focuses on shock layer radiation with the NEQAIR code and EAST shock tube facility.
Host: AME Department
More Info: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Webcast: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09Location: Seaver Science Library (SSL) - 202
WebCast Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
AME Seminar
Wed, Sep 29, 2021 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Malancha Gupta, USC
Talk Title: Initiated Chemical Vapor Deposition of Polymer Coatings and Membranes
Abstract: Initiated chemical vapor deposition (iCVD) is a solventless process that can be used to synthesize polymer films and coatings with a range of functionalities including hydrophilicity, hydrophobicity, light-responsiveness, and thermo-responsiveness. This talk will present the mechanism, capabilities, and advantages of the iCVD process. We will demonstrate that the iCVD process can be used to modify the surface properties of fibers, membranes, and microfluidic channels for applications in textiles, separations, and diagnostics. We will also demonstrate that polymers can be deposited onto low vapor pressure liquids including ionic liquids and silicone oils to fabricate ultrathin freestanding polymer films, nanoparticles, core-shell particles, and gels. We will also show that lowering the temperature of the substrate below the freezing point of the monomer leads to the formation of polymer membranes. These membranes can be deposited onto porous substrates to create hierarchical porous-on-porous structures that can enable improved filtration for water purification and sensor applications.
Biography: Malancha Gupta is the Gabilan Distinguished Professor at the Mork Family Department of Chemical Engineering and Materials Science at the University of Southern California. She received her B.S. in chemical engineering from The Cooper Union in New York City in 2002. She received her Ph.D. in chemical engineering from Massachusetts Institute of Technology in 2007 under the guidance of Professor Karen Gleason. From 2007-2009, she was a postdoctoral fellow in the department of chemistry and chemical biology at Harvard University working under the guidance of Professor George Whitesides. Her current research interests include polymer coatings and thin films, chemical vapor deposition, ionic liquids, and microfluidics. She has mentored 16 doctoral students and published 68 peer-reviewed manuscripts. She received the Jack Munushian Early Career Chair in 2013, the National Science Foundation CAREER award in 2013, and the USC Viterbi School of Engineering Junior Faculty Award in 2014. She was director of the chemical engineering program from 2018-2020 and she has served as chair of the Women in Science and Engineering (WiSE) engineering committee at USC since 2015.
Host: AME Department
More Info: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Webcast: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09Location: Seaver Science Library (SSL) - 202
WebCast Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/97427241653?pwd=UGd2aXY2b3dsQkxMdzdvcnNBMjRJZz09
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor.
