Past Seminars

11.1.24 Dr. Pinar Acar – Virginia Tech

Data-Driven Multi-Scale Design of Engineering Materials under Uncertainty

Date: November 1, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: The area of data-driven materials design has been garnering considerable interest due to the increasing need for high-performance materials in electronics, energy and structural applications, and extreme environments. The research on engineering materials and their manufacturing will potentially extend in the future to the development of new-generation composites, alloys, ceramics, and other materials for extreme environments such as hypersonics applications, fabrication of adaptive thermal response materials, energetic composites in fuel cells, thermal energy harvesting in satellites, and materials for green energy applications with the use of computational and data-driven design strategies.

In this talk, Dr. Acar will present an overview of the multi-scale computational methods developed by her research group to design metallic microstructures and mechanical metamaterials for enhanced mechanical performance. The talk will also discuss the impact of manufacturing-related uncertainty arising from the imperfections and defects during processing on the reliability and performance of these engineering materials. Additional topics will cover the integration of Artificial Intelligence (AI)/Machine Learning (ML) techniques into physics-informed material models to accelerate the design of material systems processed with conventional and additive manufacturing techniques.

Biographical Sketch: Dr. Pinar Acar is an Associate Professor at the Mechanical Engineering Department of Virginia Tech. Her research interests focus on multi-scale materials modeling, materials design, design optimization, uncertainty quantification, and machine learning. She received her Ph.D. degree in 2017 from the Aerospace Engineering Department of the University of Michigan. During her Ph.D., she developed various computational methods for studying the multi-scale modeling and design of metals under uncertainty.

Dr. Acar is the winner of the National Science Foundation (NSF) Career Award, the Air Force Office of Scientific Research (AFOSR) Young Investigator Program (YIP) Award, the Dean’s Awards of Excellence: Faculty Fellow and Outstanding New Assistant Professor Awards at Virginia Tech, Frontiers of Materials Award by The Minerals, Metals and Materials Society (TMS), and the International Amelia Earhart Fellowship, as well as the recipient of the best paper award in Non-Deterministic Approaches field in AIAA SciTech Forum 2022.  She is an elected member of technical committees in various professional societies, including the American Society of Mechanical Engineers (ASME), The Minerals, Metals & Materials Society (TMS), The U.S. Association for Computational Mechanics (USACM), and The American Institute of Aeronautics and Astronautics (AIAA).

10.18.2024 Dr. Jason Hirschey – National Renewable Energy Laboratory

Thermal Energy Storage for Grid Resilience

Date: October 18, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: The energy sector is undergoing a major transformation.  More renewable energy resources are being added to the energy grid to replace aging fossil fuel power plants and meet growing demand.  However, these renewable energy resources are more intermittent and rely on favorable weather conditions to produce energy often resulting in a misalignment of energy generation and demand.  Thermal energy storage (TES) is a powerful tool to combat this misalignment.  This talk will discuss how TES can improve the resilience of the evolving energy grid.  Near-ambient temperature TES can complement building technologies to reduce building energy usage for heating and cooling, shift energy usage from on-peak to off-peak times, and extend the capabilities of existing building heating and cooling systems.  At elevated temperatures, TES can serve as a peaking resource delivering power to the grid by discharging high grade heat to a thermal power cycle when renewable generation drops or demand rises.  As the energy grid continues to evolve, TES provides unique opportunities to further enable widespread renewable energy deployment.

Biographical Sketch: Jason Hirschey is a postdoctoral researcher in the Thermal Energy Systems group at the National Renewable Energy Laboratory in Golden, Colorado.  He received his PhD in mechanical engineering from the Georgia Institute of Technology in 2022 on near ambient temperature thermal energy storage for building heating and cooling.  His current research focuses on thermal energy and heat transfer with special emphasis on concentrated solar power and high temperature thermal energy storage for power generation.

10.11.2024 Dr. Yi Ren – Arizona State University

Two-player zero-sum differential games with one-sided information and state constraints, aka Football

Date: October 11, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: Enabling embodied intelligence requires robots to plan according to unknown and potentially adversarial intents of interacting agents. This talk will focus on one scenario where theory and methods are underdeveloped. Specifically, we study zero-sum differential games with state constraints and one-sided information, where the informed player (Player 1) has a categorical payoff type unknown to the uninformed player (Player 2). The goal of Player 1 is to minimize his payoff without violating the constraints, while Player 2 either aims to violate the state constraints or, failing that, maximize the payoff. Examples of such games include man-to-man matchup in football and missile defense scenarios. Due to the zero-sum nature, Player 1 may need to delay information release or even manipulate Player 2’s belief to take full advantage of information asymmetry, while Player 2’s strategy will need to balance all possible consequences. Existing solvers such as CFR+ (e.g., for Poker) are applicable, but are not scalable to continuous action spaces as is often the case in robotics. We will discuss efficient solvers for these games by leveraging unique structural properties of their value functions.

Biographical Sketch: Dr. Yi Ren is an Associate Professor in the Department of Mechanical and Aerospace Engineering at Arizona State University. His research spans a range of topics at the intersection of machine learning and engineering, with recent focuses on differential game theory, GenAI model attribution, and representation learning for materials. He has published in both machine learning conferences, including ICLR and ICML, and engineering journals, such as IEEE Transactions on Robotics and Acta Materialia. Dr. Ren received his Ph.D. in Mechanical Engineering from the University of Michigan in 2012 and his Bachelor’s degree in Automotive Engineering from Tsinghua University in 2007. Outside of research, he enjoys playing soccer and spending time with his children.

The Combined Use of Modeling and Large-scale Experiments in the Development of Fire Protection Solutions

Speaker: Dr. Francesco Tamanini – FM Global
Date: October 4, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: Practical fire protection challenges are often not easily amenable to solutions that can be developed from a single approach.  The tools that are more frequently used include: engineering correlations, reduced-scale physical modeling, large-scale testing, computer simulations.  The last two find wide application in addressing loss prevention questions.  Large-scale testing, however, is very expensive and not always feasible.  CFD modeling, on the other hand, is not fully reliable in the absence of experimental validation.  These limitations can be overcome by combining the two approaches.  The seminar will discuss two cases where that was done and will highlight the challenges that were encountered.

Biographical Sketch: After doing initial work on the computer modeling of fires and coordinating for several years FM’s research activities in the area of explosions, Dr. Tamanini moved in 2004 to the Consulting Research Scientist position and eventually to Sr. Research Fellow.  In his current role, he provides support to the Manager of Research, and to the entire scientific and engineering staff, on issues spanning all research topics of interest to FM.  They include: fire testing, material flammability, CFD modeling of fires and explosions, impact of natural hazards (wind, flood, earthquake) on property, risk assessment, equipment reliability, and material damage. During April 2021-June 2023 he has been the Acting Director for the Equipment, Cyber and Materials Science Area.

He has contributed original work in several technical areas:

  • extinguishment of fires by water sprays;
  • computer modeling of turbulent buoyancy controlled flames;
  • measurements of the flammability properties of materials;
  • large scale experiments on the combustion behavior of hydrogen releases into confined volumes;
  • definition of the reactivity characteristics of silane;
  • vent sizing requirements for explosions in layered vapor/air mixtures;
  • engineering tools for dust explosion protection vent sizing;
  • protection of storage of cellulose nitrate film;
  • interpretation of ceiling layer temperatures in large-scale fires; and
  • various other fire problems, as well as dust and gas explosions.

 

Franco started working at Factory Mutual Research in 1974 after receiving a Ph.D. in applied physics from Harvard University.  He also holds an MS degree in aeronautics from the California Institute of Technology and a Laurea in mechanical engineering from the Politecnico di Torino in Italy.  He has served as the Chairman of the Eastern States Section of the Combustion Institute, is the 1996 recipient of the Bill Doyle award of the AIChE, and has published numerous refereed papers and technical reports.

 

Sooting tendency measurements for formulating sustainable fuels that reduce soot emissions

Dr. Charles McEnallySpeaker: Dr. Charles McEnally – Yale University
Date: Sep 13, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: The transition from fossil fuels to sustainable fuels offers a unique opportunity to select new fuel compositions that will not only reduce net carbon dioxide emissions, but also improve combustor performance and reduce emissions of other pollutants.  A particularly valuable goal is finding fuels that reduce soot emissions.  These emissions cause significant global warming, especially from aviation since soot particles are the nucleation site of contrails.  Furthermore, soot contributes to ambient fine particulates, which are responsible for millions of deaths worldwide each year.  Fortunately, soot formation rates depend sensitively on the molecular structure of the fuel, so fuel composition provides a strong lever for reducing emissions.  Sooting tendencies measured in laboratory-scale flames provide a scientific basis for selecting fuels that will maximize this benefit.  We have developed new techniques that expand the range of compounds that can be tested by reducing the required sample volume and increasing the dynamic range.  This has many benefits, but it is particularly essential for the development of structure-property relationships using machine learning algorithms: the accuracy and predictive ability of these relationships depends strongly on the number of compounds in the training set and the coverage of structural features.

 

Biographical Sketch: Charles received a Ph.D. in Mechanical Engineering from the University of California at Berkeley in 1994, where he studied with Catherine Koshland and the late Robert Sawyer.  Since then, he has been in the Chemical Engineering Department at Yale University where he works with Professor Lisa Pfefferle.  His research interest is combustion of sustainable fuels.

 

Learning neural operators accurately, efficiently, reliably, and in one shot

dr. lu

Speaker: Dr. Lu Lu – Yale University
Date: Sep 20, 2024; Time: 2:30 PM Location: PWEB 175

Abstract: As an emerging paradigm in scientific machine learning, deep neural operators pioneered by us can learn nonlinear operators of complex dynamic systems via neural networks. In this talk, I will present the deep operator network (DeepONet) to learn various operators that represent deterministic and stochastic differential equations. I will also present several extensions of DeepONet, such as DeepM&Mnet for multiphysics problems, DeepONet with proper orthogonal decomposition or Fourier decoder layers, MIONet for multiple-input operators, and multifidelity DeepONet. I will demonstrate the effectiveness of DeepONet and its extensions to diverse multiphysics and multiscale problems, such as bubble growth dynamics, high-speed boundary layers, electroconvection, hypersonics, geological carbon sequestration, full waveform inversion, and astrophysics. Deep learning models are usually limited to interpolation scenarios, and I will quantify the extrapolation complexity and develop a complete workflow to address the challenge of extrapolation for deep neural operators. Moreover, I will present the first operator learning method that only requires one PDE solution, i.e., one-shot learning, by introducing a new concept of local solution operator based on the principle of locality of PDEs.

Biographical Sketch: Dr. Lu Lu is an Assistant Professor in the Department of Statistics and Data Science at Yale University. Prior to joining Yale, he was an Assistant Professor in the Department of Chemical and Biomolecular Engineering at University of Pennsylvania from 2021 to 2023, and an Applied Mathematics Instructor in the Department of Mathematics at Massachusetts Institute of Technology from 2020 to 2021. He obtained his Ph.D. degree in Applied Mathematics at Brown University in 2020, master’s degrees in Engineering, Applied Mathematics, and Computer Science at Brown University, and bachelor’s degrees in Mechanical Engineering, Economics, and Computer Science at Tsinghua University in 2013. His current research interest lies in scientific machine learning, including theory, algorithms, software, and its applications to engineering, physical, and biological problems. His broad research interests focus on multiscale modeling and high performance computing for physical and biological systems. He has received the 2022 U.S. Department of Energy Early Career Award, and 2020 Joukowsky Family Foundation Outstanding Dissertation Award of Brown University. He is also an action editor of Journal of Machine Learning.

MEAM Seminar Series – Lightning Talks: Meet Our Faculty – 9.6.2024

Three MEAM faculty will present their research. Come and learn about their exciting research, ask questions, and learn about research opportunities.

Prof. Hongyi Xu joined the University of Connecticut in February 2019 as an Assistant Professor in Mechanical Engineering. His research interests include Computational Design and Deep Generative Design of Microstructures and Structures, Design for Digital/Cyber Manufacturing, and Uncertainty Quantification. Prior to joining UConn, Dr. Xu received his PhD from Northwestern University in 2014, and worked for Ford Research and Advanced Engineering from 2014 to 2019. Dr. Xu’s research contributions have been recognized with the 2024 ASME Design Automation Young Investigator Award, the NSF CAREER Award, and invited participation in the 2023 National Academy of Engineering EU-US Frontiers of Engineering Symposium.

 

 

Prof. Chao Hu received his B.E. in Engineering Physics from Tsinghua University in Beijing, China, in 2007 and his Ph.D. in Mechanical Engineering from the University of Maryland, College Park in 2011. He worked first as a Senior Reliability Engineer and then as a Principal Scientist at Medtronic in Minnesota from 2011 to 2015; he joined the Department of Mechanical Engineering at Iowa State University in 2015 and worked first as an Assistant Professor and then as an Associate Professor from 2015 to 2022. He is currently a Collins Aerospace Professor in Engineering Innovation and an Associate Professor in the Department of Mechanical Engineering at the University of Connecticut. Dr. Hu’s research interests are engineering design under uncertainty, lifetime prediction of lithium-ion batteries, and prognostics and health management. He serves as the Associate Editor for Engineering Optimization, representing the North American region, a Review Editor for Structural and Multidisciplinary Optimization, and an Associate Editor for the ASME Journal of Mechanical Design and IEEE Sensors Journal.

 

ji ho jeon

Prof. Ji Ho Jeon joined our school as an Assistant Professor in August 2024. He earned his B.S. in Automotive Engineering from the University of Bath in 2014, followed by a Ph.D. in Mechanical Engineering from Seoul National University (SNU) in 2021. He further advanced his academic career as a postdoctoral fellow at SNU from 2021 to 2022 and as a research engineer at the Georgia Institute of Technology from 2023 to 2024. His research spans a diverse array of areas, including high-rate and large-scale composite manufacturing processes, recycling and repair of composite materials, and metal-composite joining processes. Additionally, he has expanded his research portfolio to include metal additive manufacturing processes and innovative surface post-processing techniques.

Droplets under Extreme Conditions: A shocking story

Abstract

I will first present a portable setup to generate shock waves using the exploding wire technique. Subsequently, I will showcase how droplets of various kinds (liquid metal, water, and polymeric liquids) interact and breakup in the shock wave and associated flow. I will also show the various instabilities that develop prior to breakup that are universal in nature. Lastly, I will showcase some results on shock-droplet flame interactions with analyses on flame extinction and droplet breakup.

Biographical Sketch

Prof. Saptarshi Basu received his PhD in Mechanical Engineering from University of Connecticut in 2007 with Prof. B. M Cetegen before joining University of Central Florida as an Assistant Professor. In 2010, he relocated to India and joined the prestigious Indian Institute of Science in Bangalore where he is currently the Pratt and Whitney Chair Professor in the Department of Mechanical Engineering.

Prof. Basu primarily works on multiphase systems, especially droplets at multiple length and timescales across multiple application domains ranging from surface patterning to combustion. Recently Prof. Basu have done extensive research on transmission of aerosols during COVID and on the efficacy of facemasks. His research marries fundamental aspects of classical fluid mechanics like vortex dynamics and swirling flows and the more interdisciplinary aspects of interfacial transport as in droplets to offer unprecedented insights into multiphase systems.

He is a fellow of Indian National Academy of Engineering, ASME, Institute of Physics, Royal Aeronautical Society and Royal Society of Chemistry. Prof. Basu is the recipient of DST Swarnajayanti Fellowship (equivalent of PECASE) in Engineering. Prof. Basu is a co-founder of a Biotech startup specializing in AI based Point of Care Diagnostics and a technical advisor to a deep tech startup involved in micro gas turbines. Prof. Basu serves as an editor/guest editor of several journals like Nature-scientific reports, Experiments in Fluids and European Physical Journal Special Topics. Prof. Basu’s research is extensively funded by Department of Defence, Indian Space Research Organization, Department of Science and Technology, Indo-German Science and Technology Center, Indo-US Clean Energy Center, NSF and industries like Siemens and Tata Motors. Prof. Basu has guided more than 20 PhD students in his career and published over 200 journal articles including many in Journal of Fluid Mechanics, Physics of Fluids, Combustion & Flame, Langmuir, Proc. Roy. Soc. etc.

Mechanistic Interactions at Scale in Energy Storage

Abstract: Advances in electrical energy storage systems are critical for vehicle electrification, renewable energy integration into the electric grid, and electric aviation. Recent years have witnessed an urgent need to accelerate innovation toward realizing improved and safe utilization of high energy and power densities, for example, in lithium-ion and advanced battery chemistries. These are complex, dynamical systems that include coupled processes encompassing electronic, ionic, and solid-state diffusive transport, electrochemical reactions at electrode/electrolyte interfaces, mechanical stress generation, and thermal transport in porous electrodes. This presentation will highlight the importance of the underlying mechanistic interactions at scale in the design of novel paradigms in exemplar energy storage architectures.

Biographical Sketch: Partha P. Mukherjee is a Professor of Mechanical Engineering and a University Faculty Scholar at Purdue University. His prior appointments include Assistant Professor and Morris E. Foster Faculty Fellow of Mechanical Engineering at Texas A&M University (2012-2017), Staff Scientist at Oak Ridge National Laboratory (2009-2011), Director’s Research Fellow at Los Alamos National Laboratory (2008-2009), and Engineer at Fluent India (currently Ansys Inc., 1999-2003). He received his Ph.D. in Mechanical Engineering from Pennsylvania State University in 2007. His awards include Scialog Fellows’ recognition for advanced energy storage, University Faculty Scholar and Faculty Excellence for Early Career Research awards from Purdue University, The Minerals, Metals & Materials Society Young Leaders Award, and invited presentations at the U.S. National Academy of Engineering Frontiers of Engineering symposium and Gordon Research Conference – Batteries, to name a few. His research interests are focused on mesoscale physics and stochastics of transport, chemistry, and materials interactions, including an emphasis on the broad spectrum of energy storage and conversion.