Events for November
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AME Seminar
Wed, Nov 04, 2020 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Faisal Amlani, USC
Talk Title: Novel High-Performance Numerical Methods for Problems in Solids, Fluids and Their Interactions: Predictions and Insights into the Underlying Physics
Abstract: This talk discusses efforts to study wave-like phenomena in realistic applications through the development of new high-order methodologies for the numerical analysis of the partial differential equations (PDEs) that govern both linear and nonlinear behavior. These techniques include new Fourier-based methods in the time-domain as well as adaptive boundary element methods in frequency-space, where the ultimate goal is to provide fast, stable and physically-faithful resolution of the underlying mechanical dynamics. With an eye towards mutual validation of both simulation and experiment, these tools will be demonstrated through some of the collaborative scientific problems that have inspired them, including those in materials science (ultrasonic non-destructive testing), cardiovascular medicine (hemodynamic waves) and geophysics (supershear ruptures and tsunami generation).
Biography: Faisal Amlani received his BA from Rice University and his PhD from Caltech, both in applied mathematics. His doctoral work was awarded the Caltech W.P. Carey Prize and the Caltech Demetriades Prize for the most outstanding dissertation in mathematics and seismo-engineering, respectively. After some years working as an experimentalist and engineer at an R&D aerospace startup in Los Angeles, he returned to academia by way of France through postdocs at Sorbonne University and the Institut Polytechnique de Paris. He is currently a Postdoctoral Scholar-Research Associate in the Department of Aerospace & Mechanical Engineering at USC.
Host: AME Department
More Info: https://usc.zoom.us/j/98031374607
Webcast: https://usc.zoom.us/j/98031374607Location: Online event
WebCast Link: https://usc.zoom.us/j/98031374607
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/98031374607
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AME PhD Student Seminar
Fri, Nov 06, 2020 @ 03:00 AM - 04:00 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Shilpa Vijay, USC AME PhD Student
Talk Title: Interfacial thermal transport in partially porous channel flow at turbulent flow regimes
Abstract: We investigate interfacial thermal transport in a partially porous channel via laboratory experiments to evaluate the effect of porous medium microstructure at varying Reynolds numbers. Previous direct numerical simulations for partially porous channel flow indicate that large vortex structures enhance turbulent heat transfer at the porous medium-unobstructed
flow interface. Commercially-available Aluminum foams with nominal pore sizes 10 ppi and 40 ppi are attached to a heater block and placed in a forced convection arrangement adjacent to an unobstructed channel. Measurements of pressure drop and temperatures are made across the porous section for bulk Reynolds number varying from 500 to 1500 to characterize friction factors and Nusselt numbers. Heat transfer efficiency with respect
to pumping power requirements is evaluated. Particle Image Velocimetry (PIV) measurements made at a subset of these Reynolds numbers are being analyzed to test for the emergence of interfacial vortex structures, and quantify their effect on interfacial thermal transport.
Biography: Shilpa Vijay is a Ph.D. student under Professor Mitul Luhar. Her research focuses on characterizing thermal transport over porous interfaces in turbulent regimes. Shilpa has a B.S. in Civil Engineering from College of Engineering Pune in India (2016), and an M.S. in Mechanical Engineering from USC (2018).
Host: AME Department
More Info: https://usc.zoom.us/j/92144809085
Audiences: Everyone Is Invited
Contact: Christine Franks
Event Link: https://usc.zoom.us/j/92144809085
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Advanced Manufacturing Seminar Series
Fri, Nov 06, 2020 @ 11:30 AM - 01:00 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Ajay Malshe, Purdue
Talk Title: Nature's Tool Box for Smart Manufacturing Enterprise
Abstract: Speaker will discuss simplicity, elegance, and robustness as foundations for innovations for equity in a smart and inclusive enterprise. This talk will discuss functions, structures, and resilience demonstrated by nature in a sustainable ecosystem. Speaker will share multiple examples to illustrate lessons materials and manufacturing disciplines can learn and apply to advance state of the art for better multifunctionality,
adaptability, survivability, and sustainability.
Biography: Please see attached flyer.
More Info: https://usc.zoom.us/webinar/register/WN_Og2AM47xQPmuDYgkAP-3NA
Webcast: https://usc.zoom.us/webinar/register/WN_Og2AM47xQPmuDYgkAP-3NAMore Information: Adv Mfg Seminar Fall 2020_Ajay Malshe.pdf
Location: Online event
WebCast Link: https://usc.zoom.us/webinar/register/WN_Og2AM47xQPmuDYgkAP-3NA
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/webinar/register/WN_Og2AM47xQPmuDYgkAP-3NA
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AME Seminar
Wed, Nov 11, 2020 @ 03:30 PM - 04:30 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Mark Hodes, Tufts University
Talk Title: Asymptotic Nusselt Numbers for Internal Flow in the Cassie State and Their Application to Thermal Management of Electronics
Abstract: We consider laminar, fully-developed, Poiseuille flows of liquid in the Cassie state through diabatic, parallel-plate microchannels symmetrically textured with isoflux ridges. Through the use of matched asymptotic expansions we analytically develop expressions for dimensionless (apparent hydrodynamic) slip lengths and variously-defined Nusselt numbers. Our small parameter (ε) is the pitch of the ridges divided by the height of the microchannel. When the ridges are oriented parallel to the (fully developed) flow, we quantify the error in the Nusselt number expressions in the literature and we provide a new closed-form result. The latter is accurate to O(ε2) and valid for any solid (ridge) fraction, whereas those in the current literature are accurate to O(ε) and break down in the important limit when solid fraction approaches zero. When the ridges are oriented transverse to the (periodically fully-developed) flow, the error associated with neglecting inertial effects to find the slip length is shown to be O(ε3Re) where Re is the channel-scale Reynolds number based on its hydraulic diameter. The corresponding Nusselt number expressions are new and their accuracy is shown to be dependent on Reynolds number, Peclet number and Prandtl number in addition to ε. They're compared to numerical results from the literature. In concluding this talk, we will show how the results can be used to design enhanced liquid-metal cooling solutions for microelectronics.
Biography: Marc Hodes earned his BS, MS, and PhD degrees in Mechanical Engineering from the University of Pittsburgh, the University of Minnesota and the Massachusetts Institute of Technology, respectively. He spent 10 years at Bell Labs Research (Murray Hill, NJ) and has spent extended periods in residence at the National Institute of Standards and Technologies (NIST), the University of Limerick and Imperial College London. He joined the Department of Mechanical Engineering at Tufts University in 2008 where he is a Professor and the Director of Graduate Studies. His Groups research there has been funded by government agencies, e.g., NSF, DARPA and DoE, and industry, e.g., Huawei and Google. Research interests are in Transport Phenomena and, over the course of his career, four thematic areas have been addressed: 1) the thermal management of electronics, 2) mass transfer in supercritical fluids, 3) analysis of thermoelectric modules, and 4) momentum, heat, mass and charge transport in the presence of apparent slip. Professor Hodes is the sole- or co-author of 50 papers in archival journals on these subjects. He is also a co-inventor on 15 issued US patents. His current research lies in three areas. First, analytical solutions for Poiseuille and Nusselt numbers for liquid flows over diabatic structured surfaces that capture, e.g., the effects of curvature, thermocapillary stress and/or evaporation and condensation along menisci, are being developed. This thread is in the context of the Red Lotus Project, a collaboration with applied mathematicians at Imperial College London. Secondly, a series of experiments to measure densities, molecular and Soret diffusion coefficients and mass transfer rates in alcohol-carbon dioxide solutions at supercritical conditions relevant to the drying of aerogels are being conducted. Thirdly, a numerical method for the optimization of heat sinks is under development. The latter was recently spun out of Tufts University as a software product by a start-up company, Transport Phenomena Technologies, LLC, co-founded by Professor Hodes, per NSF SBIR funding.
Host: AME Department
More Info: https://usc.zoom.us/j/94808927541
Webcast: https://usc.zoom.us/j/94808927541Location: Online event
WebCast Link: https://usc.zoom.us/j/94808927541
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/j/94808927541
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AME PhD Student Seminar
Fri, Nov 13, 2020 @ 03:00 PM - 04:00 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Mark Hermes, USC AME PhD Student
Talk Title: Pentaradial sea stars generate downforce
Abstract: Intertidal sea stars often function in environments with extreme hydrodynamic loads that can compromise their ability to remain attached to surfaces. While behavioral responses such as burrowing into sand or sheltering in rock crevices can help minimize hydrodynamic loads, previous work shows that sea stars also alter body shape in response to flow conditions. This morphological plasticity suggests that sea star body shape may play an important hydrodynamic role. In this study, we measured the fluid forces acting on surface-mounted sea star and spherical dome models in water channel tests. All sea star models created downforce, i.e., the fluid pushed the body towards the surface. In contrast, the spherical dome generated lift. We also used Particle Image Velocimetry (PIV) to measure the midplane flow field around the models. Control volume analyses based on the PIV data show that downforce arises because the sea star bodies serve as ramps that divert fluid away from the surface. These observations are further rationalized using force predictions and flow visualizations from numerical simulations. The discovery of downforce generation could explain why sea stars are shaped as they are: the pentaradial geometry aids attachment to surfaces in the presence of high hydrodynamic loads.
Biography: Mark Hermes is a Ph.D. student advised by Dr. Mitul Luhar working in the Fluid-Structure Interactions Lab at University of Southern California (USC). His research explores the intersection of underwater crawling and hydrodynamic shape optimization for surface-attached bodies. Mark received his B.S. in Mechanical Engineering at the University of Texas at Austin and his M.S. at USC.
Host: AME Department
More Info: https://usc.zoom.us/j/92144809085
Audiences: Everyone Is Invited
Contact: Christine Franks
Event Link: https://usc.zoom.us/j/92144809085
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Advanced Manufacturing Seminar
Fri, Nov 20, 2020 @ 10:00 AM - 11:30 AM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Hangbo Zhao, USC
Talk Title: Unconventional Manufacturing of 3D Micro- and Mesostructures: From Strain-Engineered Growth to Mechanically Guided Assembly
Abstract: The growing availability of methods for 3D manufacturing has implications across diverse areas ranging from energy systems to microelectronics, yet few techniques offer the necessary capabilities in geometric complexity, materials compatibility and design versatility. In this talk, I will discuss two novel manufacturing approaches to creating 3D functional material systems that are not feasible by conventional manufacturing methods: 1) strain-engineered growth of complex 3D carbon nanotube microarchitectures, and 2) mechanically guided 3D assembly of a broad range of functional materials and electronics. I will show how strain-engineered growth of carbon nanotubes, in combination with conformal coatings, enables direct formation of hierarchically structured surfaces with tailorable mechanical and interfacial properties for controlling liquid wetting and adhesion. Next, I will describe novel manufacturing technologies that exploit structural buckling and local twisting to create morphable 3D micro- and mesoscale structures, and show their applications as optical metamaterials and as electronic scaffolds in tissue-on-chip systems.
Biography: Dr. Hangbo Zhao is an assistant professor in the Department of Aerospace and Mechanical Engineering at USC. His focus areas include micro/nano manufacturing, bio-integrated electronics, engineered surfaces, and active/smart materials. Prior to joining USC, he was a postdoctoral researcher in the Center for Bio-Integrated Electronics at Northwestern University, where he worked on multifunctional 3D materials systems and bio-integrated electronics for applications in tissue engineering and healthcare. He received his Ph.D. degree in the Department of Mechanical Engineering at MIT in 2017 on developing engineered, hierarchical surfaces for controlling liquid wetting and adhesion. His research has been published in journals including Advanced Materials, Proceedings of the National Academy of Sciences (PNAS), and Nano Today, and highlighted by Nature Nanotechnology and PNAS, His awards include the Materials Research Society (MRS) Best Poster Award (2014) and Outstanding Poster Award for the International Conference of the Polymer Processing Society (2015).
Host: AME Department
More Info: https://usc.zoom.us/webinar/register/WN_I7Rzv2KHQXeWKqDmB83P-g
Webcast: https://usc.zoom.us/webinar/register/WN_I7Rzv2KHQXeWKqDmB83P-gLocation: Online event
WebCast Link: https://usc.zoom.us/webinar/register/WN_I7Rzv2KHQXeWKqDmB83P-g
Audiences: Everyone Is Invited
Contact: Tessa Yao
Event Link: https://usc.zoom.us/webinar/register/WN_I7Rzv2KHQXeWKqDmB83P-g
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AME PhD Student Seminar
Fri, Nov 20, 2020 @ 03:00 PM - 04:00 PM
Aerospace and Mechanical Engineering
Conferences, Lectures, & Seminars
Speaker: Vamsikrishna Chinta, USC AME PhD Student
Talk Title: Reconstructing the time evolution of wall-bounded turbulent flows from non-time-resolved PIV measurements
Abstract: Particle image velocimetry (PIV) systems are often limited in their ability to fully resolve the spatiotemporal fluctuations inherent in turbulent flows due to hardware constraints. In this study, we develop models based on rapid distortion theory (RDT) and Taylor's hypothesis (TH) to reconstruct the time evolution of a turbulent flow field in the intermediate period between consecutive PIV snapshots obtained using a non-time resolved system. The linear governing equations are evolved forward and backward in time using the PIV snapshots as initial conditions. The flow field in the intervening period is then reconstructed by taking a weighted sum of the forward and backward estimates. This spatiotemporal weighting function is designed to account for the advective nature of the RDT and TH equations. Reconstruction accuracy is evaluated as a function of spatial resolution and reconstruction time horizon using direct numerical simulation data for turbulent channel flow from the Johns Hopkins Turbulence Database. This method reconstructs single-point turbulence statistics well and resolves velocity spectra at frequencies higher than the temporal Nyquist limit of the acquisition system. Reconstructions obtained using a characteristics-based evolution of the flow field under TH prove to be more accurate compared to reconstructions obtained from numerical integration of the discretized forms of RDT and TH. The effect of measurement noise on reconstruction error is also evaluated.
Biography: Vamsikrishna Chinta is a PhD student working with Prof. Mitul Luhar. His research focuses on turbulent flow reconstruction using physics-based models. Prior to joining USC as a PhD student, Vamsikrishna received his masters from Indian Institute of Science (IISc) Bangalore, and bachelors from National Institute of Technology (NIT) Calicut, both in Mechanical Engineering.
Host: AME Department
More Info: https://usc.zoom.us/j/92144809085
Audiences: Everyone Is Invited
Contact: Christine Franks
Event Link: https://usc.zoom.us/j/92144809085
