National Institute of Aerospace
Computational Fluid Dynamics Seminar

A place to share ideas and problems for barrier-breaking developments

Facebook share

▶ E-mail Subscription

Follow the announcement blog
to receive announcements and
reminders via e-mail.

▶ Contacts

Boris Diskin   [ E-mail ]
Hiroaki Nishikawa   [ E-mail ]
▶ Past Seminars

    Season 3 (2013-2014)
    Season 2 (2012-2013)
    Season 1 (2011-2012)
▶ NIA Researchers
Boris Diskin, Ph.D.  
Research Fellow, NIA
Research Associate Professor,
Mechanical and Aerospace Engineering,
University of Virginia

Adjoint-based optimization methods, Finite-volume discretizations, Multigrid methods on structured/unstructured grids
Web | E-mail
Hiroaki Nishikawa, Ph.D.  
Sr. Research Scientist, NIA

Viscous/inviscid discretization and convergence acceleration methods for unstructured grids
Web | E-mail | CFD Notes                 View Hiroaki Nishikawa's LinkedIn profile Follow HiroNishikawa on Twitter
Matteo Parsani, Ph.D.  
Postdoctoral Fellow at NASA LaRC

high-order accurate methods for large-eddy simulation and aeroacoustics, efficient explicit and implicit time integrators and acceleration techniques for compressible flows
| E-mail
Sriram Rallabhandi, Ph.D.  
Sr. Research Engineer, NIA

Aircraft Design, Sonic Boom Modeling, Multi-Disciplinary Design Optimization, Aerodynamic Analysis, Computational Fluid Dynamics, Reduced Order Modeling and Model Order Reduction
Web | E-mail
Balaji Shankar Venkatachari, Ph.D.  
Postdoctoral Fellow, University of Alabama at Birmingham

Resident at the NASA Langley Research Center in the Computational AeroSciences Branch, working on numerical algorithm development, Hypersonics, TPS modeling (continuum and multi-scale modeling), and CAA.
▶ Faculties in Residence
Li-Shi Luo, Ph.D.  
The Richard F. Barry Jr. Distinguished Endowed Professor (in Residence, NIA)
Mathematics and Statistics,
Old Dominion University

Kinetic methods for CFD, Nonequilibrium flows, Complex fluids
Web | E-mail
Bill Moore, Ph.D.  
Professor in Residence, NIA
Atmospheric & Planetary Sciences,
Hampton University

Thermal Evolution of Planet and Satellite Inteiors, Dynamical Evolution of Planets and Satellites, Coupled Atmosphere-Interior Modeling of Planets, What Makes a Planetary Body Habitable?
Web | E-mail
free counter

NIA CFD Seminar Schedule

Click here to view the full list of videos.
Click the camera icon below to go directly to the video for each seminar.

12-02-2014   11:00am - Noon (EST)   NIA Room 137      webcast(not ready yet)

Entropy stable wall boundary conditions for the compressible Navier-Stokes equations

Non-linear entropy stability and a summation-by-parts framework are used to derive entropy stable wall boundary conditions for the compressible Navier-Stokes equations. A semi- discrete entropy estimate for the entire domain is achieved when the new boundary condi- tions are coupled with an entropy stable discrete interior operator. The data at the boundary are weakly imposed using a penalty flux approach and a simultaneous-approximation-term penalty technique. Although discontinuous spectral collocation operators are used herein for the purpose of demonstrating their robustness and efficacy, the new boundary conditions are compatible with any diagonal norm summation-by-parts spatial operator, including fi- nite element, finite volume, finite difference, discontinuous Galerkin, and flux reconstruction schemes. The proposed boundary treatment is tested for three-dimensional subsonic and supersonic flows. The numerical computations corroborate the non-linear stability (entropy stability) and accuracy of the boundary conditions.

[ presentation file (pdf) ] Matteo Parsani

Speaker Bio: Dr. Matteo Parsani is currently a Post-doctoral Fellow at NASA Langley Research Center, working with Dr. Mark H. Carpenter. Prior to this he was a Post-doctoral Researcher at KAUST, working in the group of Professor David Ketcheson. He received his Ph.D. in Mechanical and Aerospace Engineering from Free University of Brussels in December 2010. His research interests include high-order accurate methods for large-eddy simulation and aeroacoustics, efficient explicit and implicit time integrators and acceleration techniques for compressible flows. In 2011 his PhD thesis was selected among the best National Ph.D. theses to be presented at the ECCOMAS Olympiad workshop in Athens.

10-06-2014   1:00pm - 2:00pm (EDT)   NIA Room 101      video not available (realtime webcast only)

Recent Applications of Overset Mesh Technology in SC/Tetra

Software Cradle has introduced overset mesh technology to SC/Tetra since 2007, and we are dealing with a lot of demands from industries using the technology. This is a necessary function for flow simulation with moving components in complex geometries, which is not uncommon in real products. SC/Tetra's overset technology has been improved continuously, and is now able to be coupled with free-surface analysis, flow-structure interaction and dynamical moving components (6DOF). In the latest version, a special treatment for analyses of the flow in piston engines was introduced. The treatment achieves practical accuracy for mass conservation in the cylinder.

[ presentation file (pdf) ] Tomohiro Irie

Speaker Bio: Tomohiro Irie is Assistant Manager of Software Engineering Department at Software Cradle Co., Ltd. in charge of SC/Tetra's solver component.

09-09-2014   11:00am - noon (EDT)   NIA Room 137      video

Numerical Simulations of General Conservation Laws Using the Space-Time Conservative CESE Method

Governing equations of most engineering disciplines can be written as general conservation laws by enforcing mass, momentum, and energy balances. Modern computational methods are devised to provide accurate solutions to these conservation laws in the discretized space. The space-time conservation element solution element (CESE) method introduced in 1990s is a numerical framework for general conservation laws designed to provide discretized solutions in the space-time domain with considerations to ensure accuracy and robustness. The CESE method is constructed based on a non-dissipative, space time inversion invariant core scheme. Numerical dissipations are added as required. Discretized equations for dependent variables and high derivatives are formulated by enforcing both local and global conservations. It can be shown that fundamental quantities such as mass, momentum, and energy are strictly conserved both in the local conservation elements as well as the entire computational domain. To handle solutions with discontinuities, the integration volumes have interfaces that only encompass the smooth regions where solution polynomials are valid. With these constructs, the CESE numerical framework is free of ad-hoc reconstructions of physical quantities associated with interfacial discontinuity or approximations of kinetic energy. This talk discusses the fundamental concepts and development of the CESE framework with primary focus on 3D Navier-Stokes computations. High fidelity simulations of problems with multiple temporal/spatial-scales and physics are tackled with time accurate local time-stepping and high-order frameworks for unstructured meshes. Applications of the CESE method in other disciplines outside of NASA will be briefly discussed.

[ presentation file (pdf) ] Chau-Lyan Chang

Speaker Bio: Dr. Chau-Lyan Chang is a research scientist from the Computational AeroSciences Branch at NASA Langley Research Center. His primary research interest is in unstructured mesh CFD methods and code development. He also works on numerical computations of boundary layer stability and transitions. He actively maintains LASTRAC software and interacts with users from academia and industry. .

08-27-2014   11:00am - noon (EDT)   NIA Room 101      video

Structural and Multidisciplinary Design Optimization of Aircraft with Next-Generation Lightweight Materials

The use of advanced lightweight structures has enabled significant performance improvements for the present generation of transport aircraft. New structural materials, manufacturing techniques and multi-functional structural technologies will lead to even greater improvements for future aircraft. These new technologies give engineers greater flexibility to tailor aircraft structures to meet stringent design requirements. However, the large design space associated with this flexibility can be difficult to navigate since there is a limited knowledge base to help guide design decisions. Advanced computational design methods that employ high-fidelity structural and multidisciplinary analysis are key tools to help engineers understand the complex trade-offs inherent in aircraft design, especially in the context of advanced structural technologies. In this seminar, I will present our work on structural and aerostructural optimization that begins to address these challenges. To meet the computational demands of high-fidelity simulation and design, we use gradient-based design optimization techniques in conjunction with parallel computational methods and efficient adjoint-based derivative evaluation. To illustrate our efforts in these areas, I will describe the development of our in-house parallel finite-element code designed for multidisciplinary analysis and gradient-based optimization of composite structures called the Toolkit for the Analysis of Composite Structures (TACS). To demonstrate the capabilities of our structural and aerostructural design optimization framework, I will present the results of a study comparing the design of metallic and composite wings for a large transport aircraft. These results will show the benefits of using an integrated, gradient-based aerostructural analysis and design optimization framework.

[ presentation file (pdf) ] Graeme Kennedy

Speaker Bio: Dr. Graeme Kennedy is an Assistant Professor in the School of Aerospace Engineering at the Georgia Institute of Technology where he leads his research group focused on developing novel design optimization methods for structural and multidisciplinary aerospace systems. Before joining the Georgia Tech faculty, he worked as a Postdoctoral Research Fellow at the University of Michigan in the Multidisciplinary Design Optimization lab. He received his Ph.D. from the University of Toronto Institute for Aerospace Studies (UTIAS) under the supervision of Prof. Joaquim R.R.A. Martins in 2012 and hisM.A.Sc. from UTIAS under the supervision of Prof. Jorn Hansen in 2007. He received his undergraduate degree in Aerospace Engineering from the University of Toronto in 2005. A complete list of papers and ongoing projects is available on Dr. Kennedy's website:

08-26-2014   11:00am - noon (EDT)   NIA Room 137      video

First-, Second-, and Third-Order Hyperbolic Navier-Stokes Solver

Is it possible that a third-order CFD solver is less expensive on a given grid than a conventional second-order solver? No, it is impossible because a higher-order scheme requires more work on the same grid. However, as history demonstrates, it only takes a radical idea to turn the impossible into the possible. This talk will investigate whether the hyperbolization of the viscous terms is radical enough to make it happen. The Navier-Stokes equations are made hyperbolic, discretized by first, second, and third-order finite-volume schemes with upwind fluxes, and solved by a fully implicit solver: Newton's method for the first-order scheme, and a defect correction method for others. The developed solver will be compared with a conventional second-order solver for some simple but realistic viscous flow problems, focusing on computation time and accuracy especially in the viscous stresses and heat fluxes on fully unstructured viscous grids.

[ presentation file (pdf) ] Hiro Nishikawa

Speaker Bio: Dr. Hiro Nishikawa is Associate Research Fellow, NIA. He earned Ph.D. in Aerospace Engineering and Scientific Computing at the University of Michigan in 2001. He then worked as a postdoctoral fellow at the University of Michigan on adaptive grid methods, local preconditioning methods, multigrid methods, rotated-hybrid Riemann solvers, high-order upwind and viscous schemes, etc., and joined NIA in 2007. His area of expertise is the algorithm development for CFD, focusing on hyperbolic methods for robust, efficient, highly accurate viscous discretization schemes.

[ Homepage | CFD book | Free CFD codes | CFD Notes ]

Relevant Publications: First, Second, and Third-Order Finite-Volume Schemes for Navier-Stokes Equations, AIAA Paper, 2014-2091. [ AIAA Paper 2014-2091 (pdf) ]

First, Second, and Third-Order Finite-Volume Schemes for Advection-Diffusion, JCP, Volume 273, 2014. [ Preprint (pdf) | Journal ]

First, Second, and Third-Order Finite-Volume Schemes for Diffusion, JCP, Volume 256, 2014 [ Preprint (pdf) | Journal ]

Copyright 2011- . National Institute of Aerospace. All rights reserved.