Students

MAE Colloquium - Spring 2017

The Aerospace Engineering Colloquium (AE 598) is a required course that satisfies the professional development component of the Master of Aerospace Engineering (MAE). MAE students are required to complete nine (9) credits of colloquium participation to satisfy the degree requirements. However, all members of the UW community are welcome to attend and participate.

Topics may include current research and advances in aerospace technology as well as other themes relevant to the professional development of aerospace engineers. To earn credit for this course, students must complete a required set of writing assignments.

Download Course Description, Grading, and Assignment Details

Spring 2017

Mondays, 4:00 - 5:00 pm
Johnson Hall, Room 102

Faculty Coordinator: Tony Waas

 

 

April 3

Krishnan Mahesh (University of Minnesota)
Professor, Aerospace Engineering and Mechanics

Talk Title:

The simulation and modeling of turbulent flows

Abstract: 

 

Our group at the University of Minnesota focuses on fundamental advances in numerical algorithms, and understanding of flow physics that allow the prediction of engineering turbulent flows.  This presentation will discuss key aspects of such simulation alongside illustrative examples. Special attention has been paid to ensuring robustness and accuracy at high Reynolds numbers without numerical dissipation. The basic ideas behind this methodology will be discussed. The predictive capability of LES will be demonstrated for complex problems; e.g. propeller crashback, cavitation and hydroacoustics. LES results will be shown to be in good agreement with experiments and used to discuss aspects of the underlying physics.  

 

Computational Fluids Laboratory 
http://www.aem.umn.edu/~kmahesh/


Speaker Bio:

 

Link: http://www.aem.umn.edu/~kmahesh/generateabout/about.html

Fellow, American Physical Society (2011) 
Taylor Award for Distinguished Research, University of Minnesota (2010)
Associate Fellow, American Institute of Aeronautics & Astronautics (2009)
Fellow, Minnesota Supercomputing Institute (2005)
McKnight Presidential Fellowship Award, University of Minnesota (2005)
Guillermo Borja Award, University of Minnesota (2005)
McKnight Land-Grant Professorship, University of Minnesota (2003)
CAREER Award, National Science Foundation (2002)
Francois N Frenkiel Award, American Physical Society (1997)
Institute Silver Medal, Indian Institute of Technology, Bombay (1989)

April 10

Thomas Jarboe (University of Washington)
Professor, Aeronautics & Astronautics

Talk Title:

Solar Dynamo

Abstract: 

 

A new model for the engine of solar magnetic activity is presented, developed through the union of foundational plasma physics and observed solar behavior, which together form a set of constraints on possible dynamo models. Key to this proposed model is the application of the process of plasma self-organization, which is shown to have a more powerful effect in the Sun than has often been assumed, and provides a feasible way to reconcile the size of the solar dynamo with the resistive diffusion timescales associated with its size. The resulting model consists of a thin, stable magnetic equilibrium covering most of the solar surface below the photosphere, arranged in a mesh within the supergranules, which is reshaped and reorganized on an 11-year half-cycle due to slow, large-scale solar activities. This periodic readjustment of the equilibrium triggers the observed magnetic activity, and the thinness of the equilibrium makes the solar dynamo under this model powerful enough to also fuel other solar phenomena, such as the chromosphere, the corona, the solar wind, and the current in the solar current sheet. A physics-based description of the solar magnetic activity is presented that agrees with observations, including the power to the chromosphere and corona, the heliospheric current sheet and its magnitude at the earth, the 180 degree flipping of the magnetic fields and the pattern of the radial magnetic field in the solar cycle, the flipping of the polar magnetic flux, sunspots, the differences of the corona during solar minimum compared to solar maximum and the plasma structure in solar prominences.


Speaker Bio

Professor Jarboe received his undergraduate degree in Engineering Physics from the University of Illinois in 1967. He worked a short time for Olin Matheson in East Alton, Illinois and then pursued a doctoral degree at the University of California, Berkeley. In 1974, he received his PhD in plasma physics. He then joined the controlled fusion research division at Los Alamos National Laboratory. He served as group leader from 1983 to 1989 where he studied a very attractive magnetic fusion confinement device called the spheromak. He spent one year beginning in 1985 doing the controlled fusion research at Culham Laboratory in England. He came to the University of Washington in 1989 as Professor of Nuclear Engineering and joined the Department of Aeronautics and Astronautics in 1992. He is a fellow of the American Physical Society.

Professor Jarboe's current research interests lie in plasma physics and controlled fusion. He is presently pursuing three plasma research interests. First, he is Director of the Plasma Science and Innovation Center (PSI-Center). The goal of the center is to develop computational predictability for improved magnetic confinement configurations with controlled fusion applications. The PSI-Center plays an important role in making fusion energy practical and in advancing plasma science in general. Second, he leads the Helicity Injected Torus (HIT) program on Campus. The HIT program investigates the formation and sustainment of fusion confinement configurations using helicity injection current drive. This method eliminates the need for the pulsed Ohmic heating transformer that is normally used and allows steady state operation. The present HIT experiment is developing constant inductive helicity injection for a spheromak. Developing an efficient current drive method for a spheromak that is compatible with good confinement would be a major advance for practical fusion energy. Finally, Professor Jarboe leads a collaboration with the Princeton Plasma Physics Laboratory, where coaxial helicity injection (CHI) current drive, developed at the UW, is being applied to the National Spherical Torus Experiment (NSTX). CHI is to be used on this major US fusion facility for plasma startup and current profile control.

April 17

Marco Ceze (Amazon Prime Air)
Research Scientist

Talk Title:

Algorithms in hp-adaptive discontinuous Galerkin for computational aerodynamics

Abstract: 

Quantitatively accurate results from realistic Computational Fluid Dynamics (CFD) simulations are often accompanied by high computational expense. Higher-order methods are good candidates for providing accurate solutions at reduced cost. However, these methods are still not robust for industrial applications. In this talk, I will present some of my research work to address this problem.

First, I present a solution advancement method that improves robustness of discontinuous Galerkin (DG) discretizations  in the iteration to the solution. The method includes physical realizability constraints in the solution path and provides the solver with the ability of circumventing non-physical regions of the solution space that can occur during the numerical transient. The method relies only on implicit time integration and it can be applied to other discretization methods.

Then, I demonstrate an hp-adaptation method that directly targets output error by locally choosing between subdividing an element or raising the approximation order. The decision is made by finding the refinement option that maximizes a merit function that involves output sensitivity and computational cost. Results in two and three dimensions show savings of up to an order of magnitude in terms of number of degrees of freedom and at least a factor of two in terms of computational time.

Lastly, I describe the development of a high-order DG, matrix-free primal and adjoint solvers for the Navier-Stokes equations. The matrix-free framework allows for the use of very high orders of approximation accuracy (e.g. 8th, 16th) at an affordable computational cost. The final goal with high-order space-time adjoints is to adaptively improve the solution-space based on estimates of output error.


Speaker Bio:

Dr. Marco Ceze is a Research Scientist at Amazon Prime Air flight controls team. Prior to Amazon, he was appointed a NASA Postdoctoral Fellowship at Ames Research Center where he worked on the Revolutionary Computational Aerosciences project under the supervision of Dr. Scott Murman at NASA’s Supercomputing Division. Marco obtained his PhD. in Aerospace Engineering at the University of Michigan under the supervision of Prof. Krzysztof Fidkowski.

April 24

Angela Schoellig (University of Toronto)
Assistant Professor at the University of Toronto Institute for Aerospace Studies
Associate Director of the Centre for Aerial Robotics Research and Education

Talk Title:

Machine Learning for Robotics: High-Performance Flight Control in Unknown and Changing Conditions

Abstract: 

 

Traditionally, motion planning and control algorithms for robots have been designed based on a-priori knowledge about the system and its environment (including models of the robot’s dynamics and maps of the environment). This approach has enabled successful robot operations in predictable environments. However, to achieve reliable and efficient robot operations in unknown, changing, and generally uncontrolled environments, we must enable robots to acquire knowledge during operation and adapt their behavior accordingly.

In my talk, I will give an overview of my group’s research activities on learning-based control for safe, high-performance flight. Our learning schemes combine ideas from control theory and machine learning, and are motivated by real-world applications of flying vehicles.

More recently, we have also applied our learning-enabled controllers to self-driving vehicles.


Speaker Bio:

 

Angela Schoellig is an Assistant Professor at the University of Toronto Institute for Aerospace Studies (UTIAS) and an Associate Director of the Centre for Aerial Robotics Research and Education (CARRE). With her team, she conducts research at the interface of robotics, controls and machine learning. Her goal is to enhance the performance, safety and autonomy of robots by enabling them to learn from past experiments and from each other. You can watch her robots, both aerial and ground vehicles, perform slalom races and flight dances athttps://www.youtube.com/user/angelaschoe.

She is the recipient of a 2017 Sloan Research Fellowship (as one of two in robotics in the US/Canada), a Ministry of Research, Innovation & Science Early Researcher Award, a Connaught New Researcher Award, and the Best Robotics Paper Award at CRV 2014. She is one of Robohub’s “25 women in robotics you need to know about (2013)”, winner of MIT’s Enabling Society Tech Competition, finalist of Dubai’s 2015 $1M “Drones for Good” competition, and youngest member of the 2014 Science Leadership Program, which promotes outstanding scientists in Canada. She has been a keynote speaker at various outreach events including TEDxUofT, Lift China, and the Girls Leadership in Engineering Experience weekend.  

Angela received her Ph.D. from ETH Zurich (with Prof. Raffaello D’Andrea), and holds both an M.Sc. in Engineering Science and Mechanics from the Georgia Institute of Technology (Prof. Magnus Egerstedt) and a Masters degree in Engineering Cybernetics from the University of Stuttgart, Germany (Prof. Frank Allgower). Her Ph.D. was awarded the ETH Medal and the 2013 Dimitris N. Chorafas Foundation Award (as one of 35 worldwide).

 

May 1

Geoffrey Spedding (University of Southern California)
Professor, Aerospace & Mechanical Engineering

Talk Title:

Old and New Problems in Low Reynolds Number Aerodynamics

Abstract: 

Aeronautics is a mature and powerful discipline, and great success has been achieved in predicting flows and designing aircraft configurations at quite large scales, where the effects of viscosity can be modeled as minor modifications to basically inviscid dynamics.  That is not the case at smaller scales, those of the new generation of drones, and of smaller birds and bats.  Here the competing inertial and viscous terms lead to a delicate balance in solutions that have extreme sensitivity to variations in boundary and initial conditions.  In this talk we will show how, in a Reynolds number regime that is only now becoming of practical interest, nominally simple problems do not necessarily have simple solutions, and how seemingly modest computational and experimental goals remain elusive.


Speaker Bio:

 

Geoffrey Spedding received his Ph.D. in 1981 from the University of Bristol, England.  He began work as a Research Associate in the Department of Aerospace Engineering at the University of Southern California in the same year, where he worked on models of insect wings and models of atmospheres and oceans. He became a full Professor in 2005, and Chair of the Aerospace and Mechanical Engineering Department in 2010.  His current research has three themes: (i) Geophysical Fluids: particularly the evolution of turbulence in oceans and atmospheres, and its relation to the persistence of wakes of islands and submarines; (ii) Advanced imagining and data analysis including accurate particle imagining velocimetry (PIV) techniques and novel 2D wavelet transforms and interpolation routines for scattered data; (iii) Aerodynamics of small flying devices, especially those where birds and bats coexist in engineering design space.  In 2010 he was elected Fellow of the American Physical Society.  In 2013 he was awarded the Chaire Joliot at ESPCI, Paris.​

 

May 8

Gretar Tryggvason (University of Notre Dame)
Viola D. Hank Professor
Chair, Aerospace & Mechanical Engineering

Talk Title:

Direct Numerical Simulations of Complex Multiphase Flows

Abstract: 

Direct numerical simulations (DNS), where every continuum length and time scale is fully resolved, allow us to follow the evolution of complex flows for sufficiently long time so that meaningful statistical quantities can be gathered. Results for relatively simple multifluid and multiphase systems with bubbles and drops in turbulent flows are now available, but new challenges are emerging. First of all, DNS of very large systems are yielding enormous amount of data that, in addition to providing physical insights, opens up new opportunities for the development of lower order models that describe the average or large-scale behavior. Recent results for bubbly flows and the application of statistical learning tools to extract closure models from the data suggest one possible strategy. Secondly, success with relatively simple systems calls for simulations of more complex problems. Multiphase flows often produce features such as thin films, filaments, and drops that are much smaller than the dominant flow scales and are often well-described by analytical or semi-analytical models. Recent efforts to combine semi-analytical models for thin films using classical thin film theory, and to compute mass transfer in high Schmidt number bubbly flows using boundary layer approximations, in combination with fully resolved numerical simulations of the rest of the flow, are described.


Speaker Bio:

 

Gretar Tryggvason is the Viola D. Hank professor at the University of Notre Dame and the chair of the Department of Aerospace and Mechanical Engineering. He received his PhD from Brown University in 1985 and was on the faculty of the University of Michigan in Ann Arbor until 2000, when he moved to Worcester Polytechnic Institute as the head of the Department of Mechanical Engineering. He moved to the University of Notre Dame in 2010. Professor Tryggvason is well known for his contributions to computational fluid dynamics; particularly the development of methods for computations of multiphase flows and for pioneering direct numerical simulations of such flows. He served as the editor-in-chief of the Journal of Computational Physics 2002-2015, is a fellow of APS, ASME and AAAS, and the recipient of several awards, including the 2012 ASME Fluids Engineering Award.

UPCOMING SPEAKERS IN SPRING 2017:

 

05.15.17 | Chris Lynch
Professor, Mechanical & Aerospace Engineering
Univ. California, Los Angeles

 

05.22.17 | Carlos Cesnik
Professor, Aerospace Engineering
Univ. of Michigan

 

05.29.17 No Speaker this week-University Holiday