Mechanical and Aerospace Engineering News

The Department of Mechanical Engineering – Engineering Mechanics Graduate Seminar:
Thursday, March 26, 2014 4:00 – 5:00 p.m. Room 103 EERC Bldg.
Dr. William de Ojeda, Navistar

Title: Relevant Research Areas in Heavy-Duty Engines

The drivers for technologies in the Heavy Duty truck market are cleaner emission regulations and higher fuel efficiency standards. This presentation will illustrate how increased engine efficiencies have been attained by more capable injection and charge air systems, while at the same time engine designers work to increase the mechanical limits of the engine to allow operation at higher compression ratios and higher peak cylinder pressures. Reduction of parasitic losses and effective designs to recover the heat energy are also active areas of development. Increased efficiency is accompanied by highly integrated emission reduction technologies. Effective operation of these aftertreatment units require strict thermal management and this presentation will provide insight from novel approaches such as provided by variable valve timing over conventional techniques that require excess fuel. Finally, the area of fuels opens new possibilities for advanced combustion modes. The use of natural gas with Diesel pilot ignition, or gasoline like fuels with Diesel, of oxygenated fuels like Dimethyl Ether represent current areas of research and development and will be briefly reviewed here.
Further advances in HD powertrains with these new fuels will require continuous aligning and successful migration of basic research into the applied work of industry.

Dr. de Ojeda is a senior engineer in Powertrain Group at Navistar where he has led several advanced engine development programs. More recently he directed Navistar’s High Efficiency Vehicle-Engine Supertruck DOE Program based on the Navistar MAXXFORCE13 engine. Dr. de Ojeda holds multiple patents and publications in the
area of electro-hydraulics, variable valve train systems, combustion and controls. He has a B.S. in Mechanical Engineering from The Cooper Union in New York, a M.S. in Mechanical and Aerospace Engineering from The University of Virginia and a Ph.D. in Mechanical and Aerospace Engineering from the Illinois Institute of Technology.

The ME-EM Graduate Seminar guest speaker on Thursday, March 20 at 4:00 in 103 EERC will be Dr. David Garren from the Naval Postgraduate School.

The title of his presentation will be ‘Signatures of Surface Moving Targets within Synthetic Aperture Radar Imagery’.

Synthetic aperture radar (SAR) enables accurate collection of imagery data in all weather conditions, day or night. SAR image formation yield well-focused imagery of geophysical scenes, since the radar signal processing uses a filtering process that is matched to the radar echoes from stationary scattering centers within the scene. However, moving targets yield a signal mismatch in the processing and thus appear defocused, wherein the majority of the smearing occurs in the radar cross-range direction. This current investigation presents methods for analytically predicting the detailed shape of the smear signatures for surface targets with arbitrary motion in spotlight SAR imagery. This analysis considers the standard collection geometry in which the radar sensor moves with constant speed and heading on a level flight path, with radar beam-pattern pointed perpendicular to the direction of flight. Examples in which a target moves with constant speed and heading yield smear shapes that are simply curved, as with a parabola. However, complicated smear shapes can be obtained for cases of non-uniform target motion, as with a target that is undergoing a braking maneuver. The current investigation develops accurate equations for predicting the shapes of mover signatures based upon input values for the target motion. This predictive capability offers the potential of providing insight into the details of the target motion based upon mover signatures that are observed within SAR imagery.

Professor Garren is an Associate Professor in the Electrical and Computer Engineering Department at the Naval Postgraduate School – National Capital Region. He has over twenty years of experience in applied research in various disciplines, including radar, image processing, and signal processing. He has over thirty-five research publications in journals and conference proceedings, and he holds seven U.S. Patents. Professor Garren received the Ph.D. degree in 1991 from the College of William and Mary.

The Department of Mechanical Engineering – Engineering Mechanics Graduate Seminar Series:
Thursday, Mar. 6, 2013 4:00 – 5:00 p.m. Room 103, EERC Bldg.
Professor Andrea Mammoli, Director of the Center for Emerging Energy Technologies, University of New Mexico

Title: Turning Power Distribution Feeders into Microgrids: Challenges & Opportunities

Photovoltaic power generation is almost at grid parity. Electric vehicles are gaining popularity. Smart meters, smart thermostats and many other clever devices are being installed at rapidly increasing rates, replacing old equipment. At the same time, every time bad weather happens, large parts of the grid fail, and days go by before normality is restored. Even houses with undamaged rooftop photovoltaic systems have no power! Our increased reliance on electricity to drive all kinds of devices and machinery has, in fact, made us more vulnerable to disruptions in service. An important reason for this state of affairs is that the grid is not taking advantage of the information that is available through these myriad devices, and is operating largely as it has been for decades. On the other hand, managing information from millions of devices is not something utility companies are able or willing to do. A possible solution is to localize both information management and distributed power generation at the distribution feeder level, turning it into a microgrid. This would be able to provide basic services when islanded from the grid, and also to provide ancillary services to the grid as needed to help prevent grid-wide disruption. The problem is one of resource management: how much local generation is needed, how much and what storage, and how is power flow managed and coordinated? Also, what are the changes to infrastructure that would be needed to make all power distribution feeders into microgrids? Some of the answers will be provided as a result of a research program that started in New Mexico several years ago at Mesa del Sol, a Greenfield development south of Albuquerque that will ultimately be the home to 100,000 residents, who will live, work and play there. Studio14, a power distribution feeder that connects various innovative distributed power system, is used as a basis for studying how we can go from 19th century power to 21st century power. In this talk, we will provide examples from several ongoing projects that show how it is possible to achieve the goal of a clean, resilient power system at reasonable cost.

Andrea A. Mammoli is Professor of Mechanical Engineering, and Director of the Center for Emerging Energy Technologies at the University of New Mexico. He also holds a secondary appointment in the Department of Electrical and Computer Engineering. Mammoli obtained his Bachelor of Engineering and Doctor of Philosophy degrees from the Department of Mechanical and Materials Engineering at the University of Western Australia. After two years as Director funded postdoctoral fellow at Los Alamos National Laboratory, in 1997 Mammoli joined the University of New Mexico as Research Assistant
Professor. Until 2004, Mammoli conducted research in flow of heterogeneous materials, using both experimental techniques (nuclear magnetic resonance, particle image velocimetry and rheometry) as well as high-performance direct numerical simulation using primarily boundary element techniques. Stimulated by a DOE-sponsored project on CO2 sequestration, and by a sabbatical year at the Università Politecnica delle Marche in Italy, in 2005 Mammoli steered his research activities to the area of energy systems, beginning with a project to refurbish and modernize the solar-assisted HVAC in the UNM Mechanical Engineering building. This initial effort spun off many related projects, dealing with the interaction between buildings and the electric power grid, especially concerning how buildings can enable higher levels of renewable energy from all sources. Mammoli collaborates with the utility industry and national laborarories (Sandia, Berkeley and Los Alamos) on various demonstration projects and testbeds designed to bring new technologies to mainstream operations.

The ME-EM Graduate Seminar guest speakers on Thurs. Feb. 27 at 4:00 in 103 EERC will be Dr. Edgar Choueiri from Princeton University.

Title: 3D Audio

Starting with a brief review of the three main methods for 3-D sound reproduction over loudspeakers: 1) Wave Field Synthesis, 2) Ambisonics, and 3) Binaural audio through two loudspeakers (BAL), we focus on recent advances with the third method. I will show that crosstalk cancellation (XTC) allows BAL to deliver to the listener the necessary cues for real 3-D audio but that it inherently imposes an intolerably high spectral coloration on the audio. I will describe recent breakthroughs, which allow producing optimized XTC filters that impose no spectral coloration. I will then discuss the two other problems that have retarded the commercialization of XTC: the fixed and single sweet spot problems. I will show how the first problem is solved through advanced head tracking; and the second problem is solved using head tracking and phased array speakers, allowing the delivery of high-spatial-fidelity 3D audio to multiple moving listeners in real listening rooms. Following the talk, there will be a demo with playback of recorded music and natural sounds.

Edgar Choueiri is Professor of Applied Physics at at the Mechanical and Aerospace Engineering Department of Princeton University, and Associated Faculty at the Department of Astrophysical Sciences, Program in Plasma Physics. He is also Director of Princeton University’s Engineering Physics Program and Director of both the university’s Electric Propulsion and Plasma Dynamics Lab and its 3D Audio and Applied Acoustics (3D3A) Lab. He is the author for more than 175 scientific publications and the recipient of numerous awards and honors. His recent work on 3D audio has been featured by BBC Radio, NPR, The New Yorker magazine, The Discovery Channel, and The Atlantic magazine. His BACCH 3D Audio technology has been licensed by Princeton University and is commercially available in consumer and professional audio products.

Mechanical Engineering – Engineering Mechanics Graduate Seminar; Thursday, Feb. 20, 2014 4:00 – 5:00 p.m. Room 103 EERC Bldg.; Steven A. Walton, PhD; Professor of History, Michigan Technological University

Title: Engineering the Past: Using Modern Engineering to Understand Historical Technologies

Amazing technical tasks have been accomplished in the past, from wonders like Stonehenge to the Wright Brothers biplane, but usually with little to no framework that we could conceive of as ‘science’. Modern engineering, on the other hand, has a vast range of scientific information with which to design and analyze new developments in technology, but it rarely stops to look back at how things worked in the past. These techniques can, however, offer great insight into historical technology, but it is often overlooked by historians who don’t know modern science and by engineers who don’t consider historical topics legitimate areas for analysis. This presentation will give a number of examples of historic technologies that have been recreated and analyzed with varying levels of engineering science, and then describe an ongoing research project on the “Origins of Firepower” that seeks to understand how early firearms were made, used, and understood. In particular, a number of research opportunities will be highlighted with regard to pre-modern gunpowder manufacture and combustion, as well as early artillery metrology and ballistics.

Dr. Walton holds degrees in Mechanical Engineering (B.S. Cornell; M.S. Caltech) and the History of Science and Technology (M.A., Ph.D ., Univ. of Toronto). He is own research on the history of technologies and the industries that made them spans the Middle Ages to the nineteenth century, and he works on both European and American topics. Most recently, he has two relevant projects underway that will appear in the talk: he is part of the Early European Guns and the Origins of Firepower research groups based in the UK and Denmark and in engaged in a series of surveys and projects to understand how gunpowder weaponry from the late 15th and 16th centuries behaved; in his work on 19th-cetntry American ordnance foundries, he is studying how the early understandings of strength of materials before the Civil War influenced artillery design and manufacture. He is long-term goal is to help find places where historical studies and engineering science can come together fruitfully to answering interesting historical questions.

The ME-EM Graduate Seminar guest speakers on Thurs. Feb. 13 at 4:00 in 103 EERC will be Dr. David Harvey from Ballard Power Systems.

Title: Challenges, Opportunities, and Open-source A perspective on Fuel Cell simulation for performance and durability

Proton Exchange Membrane Fuel Cells have been a prominent part of the alternative energy landscape for a considerable length of time. The challenges facing the technology are generally categorized into three main areas: Cost, Performance, and Durability. These three areas are for the most part largely intertwined, as changes in materials or designs that improve one area invariably have, for the most part, a negative effect on the others. Of particular focus in recent initiatives has been the catalyst layer, specifically the performance and durability of a three part system of a supporting particle, nano-catalyst, and ionomeric “binder”. To date, very few commercial numerical codes exist that can adequately describe state-of-the-art PEM fuel cell performance or durability. To a large extent this is a product of the speed at which the materials development and theoretical understanding is moving, such that commercial codes tend to lag in capability as the “investment” to stay current is immense. Open-source initiatives have become commonplace in many areas, one of which is computational fluid dynamics. The open nature of these codes has led to the development of “current” sets of theory and physics in various application areas and the community nature of the projects enables and encourages leverage in other areas of engineering and design. This methodology has been applied to the development of a free and open-source software initiative, FCAPOLLO that has been built on a free and open-source CFD package.

David is a researcher in the field of alternative energy. He has been working in the area of proton exchange membrane (PEM) fuel cells since 2002 with a focus on the development of numerical simulations for performance and durability. In 2005, David began working for Ballard Power Systems in Burnaby, BC on the development of simulation codes to predict the performance of membrane electrode assemblies (MEAs). During that time, he and his group, in coordination with researchers at Queen’s University in Kingston, Onario, were the first to develop a stoichastic technique for the direct numerical simulation of catalyst layers. This work transitioned into the U.S. Department of Energy project, “Microstructural Mitigations Strategies: Morphological Simulations and Experimental Approaches” in which a series of simulations at scales ranging from nano to macro were coupled in a multi-scale modelling methodology in order to assess and predict the performance and degradation of carbon-supported platinum nano-catalysts. His current area of foucs is on the development of the software derived from the U.S. Department of Energy Project, FC-APOLLO. FC-APOLLO is a free, open-source fuel cell design software built in the opensource CFD package
OpenFOAM (trademark of OpenCFD).