Mechanical and Aerospace Engineering News

The ME-EM Graduate Seminar speaker on Thursday, April 23 at 4:00 in 103 EERC will be Dr. Reza Tafreshi from Texas A&M University at Qatar.

The title of his presentation will be ‘Development of a Low Dimensional Two-Phase Thermal Model for Subsea Pipelines’.

Rising global energy demand has led to new operational challenges in unfamiliar environments, with higher temperature gradients. The challenges directly address safety, environmental and economic issues. Due to the low subsea temperatures and relatively higher petroleum fluid temperature in deep water pipelines, convectional heat losses occur from the petroleum fluids to the surroundings. This heat transfer is necessary to be considered, to ensure the proper flow of petroleum fluids. While conventional equivalent heat transfer models are easier to compute, they are not accurate enough to reflect the changes that would occur within a fluid due to different multiphase flow regimes and proportions. The objective is to develop a low dimensional and low computational equivalent thermal model of subsea fluids, which can predict two-phase fluid temperatures along insulated subsea pipelines. The developed heat transfer model combines the application of two-phase heat transfer coefficient model with fluid properties obtained from a low dimensional fluid model developed by our group. The presented model identifies the effect of heat transfer in subsea pipelines for two-phase fluids for normal operating and shut-down conditions. This model, when compared with industry standard software, showed that results were obtained with similar accuracy with approximately 1000 times less computational time.
Some other current research activities will be also discussed.

Reza Tafreshi received his B.Sc. and M.Sc. degrees from the K.N. Toosi University of Technology, Tehran, Iran, in 1991 and 1995, respectively, and his Ph.D. degree in mechanical engineering from the University of British Columbia (UBC), Vancouver, BC, Canada, in 2005. He was a site engineer and then a project manager at PoloDej Company, Tehran, from 1995 to 1999. From 1999 to 2000, he was a Research Engineer with the Department of Mechanical Engineering, UBC. Dr. Tafreshi was a recipient of the Michael Smith Foundation for Health Research Award, Canada, and was a postdoctoral fellow at the Department of Electrical and Computer Engineering, UBC, from 2005 to 2006. He was a Visiting Assistant Professor with Texas A&M University, College Station, TX, in 2006. In 2007, he joined Texas A&M University at Qatar, Doha, Qatar, where he is currently an Assistant Professor. His research fields include dynamic systems and controls, machine fault diagnosis, condition monitoring, and biomedical engineering.

The ME-EM Graduate Seminar speaker on Thursday, April 16 at 4:00 in 103 EERC will be Dr. Emmanuel Gdoutos, Professor at Democritus University of Thrace, Greece, Adjunct Professor at Northwestern University. The title of his presentation will be ‘Multiscale Mechanical And Fracture Characterization Of Cementitious Nanocomposites.”

Results are presented for the mechanical and fracture properties of cementitous materials reinforced with multiwall carbon nanotubes (MWCNTs) and carbon nanofibers (CNFs). The MWCNTs and CNFs were dispersed in water by applying ultrasonic energy and using a surfactant. Three-point bending tests were performed to obtain the mechanical and fracture properties. The nanomechanical stiffness of the nanocomposites was investigated by nanoindentation tests. It was found that the modulus of elasticity and flexural strength increase substantially for a reinforcement of 0.08 wt.%. Fracture mechanics characterization of these materials was also performed. The excellent reinforcing capabilities of MWCNTs and CNFs are demonstrated by a significant improvement in critical stress intensity factor and critical strain energy release rate resulting in advanced materials for civil engineering applications.

Dr. Emmanuel E. Gdoutos is Professor at the Democritus University of Thrace, Greece and Adjunct Professor at Northwestern University. He is member of European and national academies worldwide, Fellow of technical societies and received medals and awards from technical societies. Recently, a special issue of the journal Meccanica was published in his honor. He received an honorary Ph.D. from the Russian Academy of Sciences and the University of Nis, Serbia. He is author of over 300 technical papers and 17 books and editor of 18 books. He served as Editor-in-chief of Strain (2007-2010), President of the European Structural Integrity Society (ESIS) (2006-2010), chairman of the European Association for Experimental Mechanics (EURASEM) (2003-2007), President of the Society for Experimental Mechanics (SEM) (2013-2014).

The ME-EM Graduate Seminar speaker on Thursday, April 9 at 4:00 in 103 EERC will be Dr. Margot Hutchins from Sandia National Laboratory.

The title of her presentation will be ‘Building the Basis for Cybersecurity and Cyber Resilience in Critical Infrastructure’.

Increasing connectivity, use of digital computation, and off-site data storage provide potential for dramatic improvements in the effectiveness of many systems (e.g., energy, manufacturing, financial services, transportation). However, there are also risks associated with this increased connectivity as well as the volume and pervasiveness of data that are generated. The inherent trust among components of digital information and communications infrastructure provides ample opportunity for those with ill intent to do harm. Organizations have experienced cyber attacks that exfiltrate confidential and/or proprietary data, alter information to cause an unexpected or unwanted effect, and destroy capital assets. Given this complex and dynamic landscape, mitigating risk is an important strategy, but it may be necessary to ensure that critical infrastructure is resilient, that is, able to efficiently reduce both the magnitude and duration of the deviation for targeted system performance levels. Metrics and tools are needed to incorporate these considerations into existing risk management processes and to evaluate possible mitigation measures. This seminar will focus on two efforts to identify cybersecurity issues and the characteristics of cyber resilience. We will examine a framework that considers the data flows within a manufacturing enterprise and throughout its supply chain, which provides several mechanisms for identifying generic and manufacturing-specific cyber vulnerabilities. We will also consider how several existing modeling and simulation capabilities could be integrated to address resilience in the electric grid.

Dr. Margot J. Hutchins is a Senior Member of Technical Staff at Sandia National Laboratories. She currently conducts systems analysis in support of U.S. national security objectives, including cyber resilience of critical infrastructure and international engagement on the implementation of nuclear detection architectures. She received her Ph.D. from the Department of Mechanical Engineering-Engineering Mechanics at Michigan Technological University, where she focused on supporting the inclusion of the social dimension of sustainability in business, manufacturing, and design decision making by developing relevant indicators and techniques. She was a postdoctoral scholar and later a research engineer in the Laboratory for Manufacturing and Sustainability at the University of California, Berkeley. There, Dr. Hutchins had the opportunity to work with industrial, regulatory, and other stakeholders on a variety of projects, including establishment of a benchmarking methodology to support California’s cap-and-trade program and development of key sustainability performance indicators for a large retailer’s suppliers.
Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000

Dr. Margot J. Hutchins is a Senior Member of Technical Staff at Sandia National Laboratories. She currently conducts systems analysis in support of U.S. national security objectives, including cyber resilience of critical infrastructure and international engagement on the implementation of nuclear detection architectures. She received her Ph.D. from the Department of Mechanical Engineering-Engineering Mechanics at Michigan Technological University, where she focused on supporting the inclusion of the social dimension of sustainability in business, manufacturing, and design decision making by developing relevant indicators and techniques. She was a postdoctoral scholar and later a research engineer in the Laboratory for Manufacturing and Sustainability at the University of California, Berkeley. There, Dr. Hutchins had the opportunity to work with industrial, regulatory, and other stakeholders on a variety of projects, including establishment of a benchmarking methodology to support California’s cap-and-trade program and development of key sustainability performance indicators for a large retailer’s suppliers.
Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-AC04-94AL85000.