Resume

• 1997

  Chicago State University

  NASA Glenn Research Center

  Modeling plasma jets;\nDirect numerical simulation (DNS) of MHD turbulence; \nModeling plasmas for various applications ranging from plasma-enhanced chemical vapor deposition (PECVD)

  treating wounds with plasma jets to propulsion systems (hypersonic

  space

  electric propulsion (ion thruster optics

  cathode)

  plasma jets for flow control

  MPD thrusters

  magnetic nozzles

  pulsed-detonation engines

  turbomachinery); dynamics of real gases

  reacting flow systems. \n\nSimulations use spectral methods on the full Boltzmann and Maxwell equations as well as linearized Boltzmann such as the lattice-Boltzmann method (LBM).\n\nTeaching freshman engineering design

  aerospace engineering fluid physics

  senior undergrad/grad electric propulsion;\n\nEngineering education using hands-on/minds-on activities & mini-projects supplementing interactive lectures!

  Texas A&M University

  Senior Lecturer/Researcher/Aerospace Engineer

  First Year Engineering instructor;\nEngineering education research;

  Texas A&M University

  NASA Glenn Research Center

  Cleveland

  OH 44135

  Compressor Rotating Stall Dynamic Modeling with 3D

  unsteady

  viscous CFD codes\n\nWorked with University of Akron on bridging CFD with reduced-order

  nonlinear dynamic models for control designs (Ph. D. student thesis topic is an extension of research with my former doctoral student summer intern)\n\nDesigned dynamic models of General Aviation aircraft internal combustion engine mated to variable pitch propeller in visual real-time simulation environment.\n\nPlanned and instrumented flight test to validate GA propulsion system dynamic models.\n\nSupersonic Compression System Dynamic Modeling\n\n• Showed new form of unstable phenomena in simulations.\n\n• Wrote and modified unsteady

  quasi-1D

  inviscid and compressible flow codes.\n\n• Monitored contracts and grants.\n\n• Mentored 5 undergraduate and graduate doctoral interns (co-wrote papers).\n\n• Designed and conducted experiment for dynamic testing of compression systems.\n\n• Took dynamic pressure

  temperature and other flow data.\n\n• Conducted spectral analyses of dynamic testing data on compression systems.\n\nSupersonic Application of Drag Force Anemometer\n\n• Designed and conducted experiments to extend the use of drag force anemometers (drag probe) to supersonic dynamic flow measurements and derived analytical basis.\n\n• Calibrated

  took Schlieren pictures and laser shadowgraphs. AIAA Journal paper on it.

  Aerospace Engineer

  Argonne

  IL 60439

  * Modified University of Chicago and ANL Flash code: successfully ported one FLASH code to MPI and sought further improvements beyond that code’s then-design like implementing a 3D version of a domain-decomposition scheme that was more compatible with the multi-grid scheme and MPI; enabled the multi-grid and domain decomposition to run with MPI on odd or even numbers of processors on ASCI parallel super-computers\n\n* Combining pressure-dilatation correction turbulence model for hypersonic flows with multi-dimensional

  integral

  multiphase

  multi-species

  reacting

  turbulent

  viscous model for supersonic injection

  mixing and combustion for scramjet model\n\n* Modified ANL's Energy Systems division code for 2D

  integral

  multiphase

  multi-species

  reacting

  turbulent

  viscous flow analysis for EPA.

  Aerospace Engineer & Computational Fluid Dynamicist

  Argonne National Laboratory

  Teaching physics and engineering studies;\n\nResearch in bio-fluid-mechanics or hemodynamics (blood flow in carotid artery)

  bio-mechanical systems (cortical-bone in upper eye orbit)

  atmospheric and oceanic wave interaction

  turbomachinery

  reacting flows

  CFD

  algorithms such as WENO

  finite element and spectral methods;\n\nService of NASA Chicago State University (CSU) Saturday Academy for Space Science; Academic Programs Review Task Force; Equipment Review

  Curriculum

  Research Proposal Review

  Instructional Technology

  Judicial Review Committees;

  Chicago State University

  Instructional Associate Professor

  Texas A&M University

  Coordinator

  NSF REU;

  Writing proposals then directing

  coordinating

  recruiting

  organizing

  ... National Science Foundation (NSF) Research Experience for Undergraduate (REU) Sites \n\nOutreach activities

  pre-college summer camps

  synergistically using Freshman to senior engineering design projects and/or research; \n\nSupporting student researcher preparation for the Louis Stokes Alliance for Minority Participation (LSAMP) at TAMU

  College Station

  Prairie View A&M

  and TAMU-Corpus Christi; correspondingly developing Graduate Interest Group w/in STEM student organizations to increase pool of undergrads interested in graduate school!

  Texas A&M University

  ASEE

  Senior Member

  American Institute for Aeronautics and Astronautics (AIAA).

  AIAA

  Member

  American Society for Mechanical Engineers (ASME): Fluid Engineering and Turbomachinery Divisions (FED).

  ASME

  Member

  American Physical Society (APS): Fluid & Computational Physics Divisions (DCOMP and DFD)

  APS

• 1984

  Spanish

  French

  English

  Ph. D.

  Aeronautical Engineering

• 1980

  Bachelor's degree

  Aerospace

  Aeronautical and Astronautical Engineering

  AIAA

  Boston University

• Mathematica

  Aerospace Engineering

  University Teaching

  Fluid Mechanics

  Fortran

  ANSYS

  Fluid Dynamics

  Matlab

  Physics

  MPI

  Aerodynamics

  Numerical Simulation

  Engineering

  C++

  Simulations

  CFD

  Turbulence

  Fluids

  Aerospace

  Linux

  Feasibility of interactive eTextbooks with computationally intense content

  Angarita

  John E.

  Whitcomb

  John D.

  Shryock

  Kristi

  J.

  Collins

  Logan N.

  Computers in Education Division of ASEE

  Vol. 6

  No. 2

  April – June 2015.\nWe evaluate the technical feasibility of creating pedagogically valuable

  highly interactive content in eTextbooks for the purpose of education in computationally intense fields. This research was motivated by the observation that emerging eTextbook technologies could help enhance the education of engineering students. Engineers often want to experiment and to be able to quickly see meaningful results. They want to receive immediate feedback or response for their inputs. They want interactive learning tools. Engineers want trial-and-error with a realistic system

  with which they can interact

  even if it is a virtual one (think hands-on and minds-on). The most interactivity in many eTextbooks is clicking links

  resizing and rotating images

  or pausing/playing audio/video. Currently

  emerging technologies associated with eTextbooks

  and eBooks in general

  are approaching a developmental level where it is possible to provide realistic virtual systems embedded in an eTextbook environment that could help build students' physical intuition. Since students may wish to interact with simulations in real-time

  one of our feasibility tests involved the real-time rendering and simulation of different example cases of fluid flows within a sample eTextbook chapter. The simulation comes with controls that the student can use to manipulate key flow parameters to see the response of the flow field to student inputs.

  Feasibility of interactive eTextbooks with computationally intense content

  Shryock

  Kristi

  J

  Olivarez

  Laura

  120th ASEE Annual Conference and Exposition

  Atlanta

  GA

  USA.

  High School Students Learn the Basics of Rocket Science In a University Summer Camp

  Sharath S. Girimaji

  We perform direct numerical simulations of decaying magnetohydrodynamic turbulence subject to initially uniform or random magnetic fields. We investigate the following features: (i) kinetic–magnetic energy exchange and velocity field anisotropy

  (ii) action of Lorentz force

  (iii) enstrophy and helicity behavior

  and (iv) internal structure of the small scales. While tendency toward kinetic–magnetic energy equi-partition is observed in both uniform and random magnetic field simulations

  the manner of approach to that state is very different in the two cases. Overall

  the role of the Lorentz force is merely to bring about the equi-partition. No significant variance anisotropy of velocity fluctuations is observed in any of the simulations. The mechanism of enstrophy generation changes with the strength of the magnetic field

  and helicity shows no significant growth in any of the cases. The small-scale structure (orientation between vorticity and strain-rate eigenvectors) does not appear to be influenced by the magnetic field.

  Magnetohydrodynamic Turbulence Decay Under the Influence of Uniform or Random Magnetic Fields

  Gustave C. Fralick

  The purpose of this research was to develop an instrument that could provide dynamic flow parameters in supersonic propulsion research. The parameters of interest are the velocity

  velocity head

  Mach number

  and mass flow rate.

  Use of drag probe in supersonic flow

  Tanya Dugat Wickliff

  Noemi V. Mendoza Diaz

  This paper describes a Work-in-Progress (WIP) on analyses of engineering enculturation constructs and the way diverse groups adopt engineering practices as performed in the field. Studies of socialization processes by which engineering students come into engineering practices provide impetus for further study about enculturation. The studies of socialization processes investigate how students start with pre-conceived notions of successful engineers and how they could eventually adopt proper work practices actually realized in the field. In the workplace

  communication and teamwork are highly valued. Yet many engineering students value individual accomplishment and competitiveness as the tactic to succeed. Our approach seeks to quantify students’ enculturation related to engineering communications and teamwork taught in a first-year engineering course to large diverse classes at a southwestern institution. The study seeks to help understand how enculturation may contribute to the development of engineering students adopting favorable behavior and engineering practices for eventual usefulness and success in the workplace.

  Enculturation of Diverse Students to the Engineering Practices through First-Year Engineering College Experiences

  This paper presents analyses of the impact of different summer Research Experience for Undergraduate (REU) programs on diverse students from the USA and India. The study gathered and analyzed the survey data from two different REU programs in two different departments and from a college-wide program for Indian students at a research university. The REU programs were funded by the National Science Foundation (NSF) for US citizens or permanent residents while the program for Indian students was funded by the college. The data showed how much the research experiences could impact the students’ decision-making between graduate school and working in industry for both national and international students. A large majority of students came to favor the graduate education and research

  as desired by the common goals of the national and international REU programs. Students credited their learning in their summer research experience for contributing to their interest in graduate education and research. The students also noted that these are skills that they would not have acquired at their home institutions.

  Impact of Undergraduate Research Experiences on Diverse National and International Undergraduate Researchers

  NASA TM 107006

  Low-Order Nonlinear Dynamic Modeling of IC Engine-Variable Pitch Propeller System for General Aviation Aircraft

  Girimaji

  Sharath S.

  2013;8(3):031010-031010-12. doi:10.1115/1.4023323\nWe examine the complex nonlinear flow-magnetic field dynamics in magneto-hydrodynamic (MHD) turbulence. Using direct numerical simulations (DNS)

  we investigate the dynamical interactions subject to the influence of a uniform applied background magnetic field. The initial magnetic and kinetic Reynolds numbers (based on Taylor microscale) are 45 and there are no initial magnetic field fluctuations. The sum total of turbulent magnetic and kinetic energies decays monotonically. With time

  the turbulent magnetic fluctuations grow by extracting energy from velocity fluctuations. Expectedly

  the distribution of energy between kinetic and magnetic fluctuations exhibits large periodic oscillations from the equipartition state due to Alfvén waves. We perform a detailed analysis of the flow-magnetic field coupling and posit a simple model for the energy interchange. Such dynamical analysis can provide the insight required for turbulence control and closure modeling strategies.

  Characterization of Flow-Magnetic Field Interactions in Magneto-Hydrodynamic Turbulence

  Kurnchel Lee

  Sharath S. Girimaji

  The effect of an external magnetic field on the evolution of rectangular plasma jets is examined. Specifically investigated is the influence of a primarily axial magnetic field on the uniquely characteristic axis-switching phenomenon of rectangular jets and flow instabilities. The results indicate that the magnetic field decelerates the jet (more rapid spreading)

  prevents axis-switching and inhibits instabilities. The key physical mechanisms underlying the changes are (1) the ability of the magnetic field to reverse the direction of vorticity and (2) transfer of energy from kinetic to magnetic forms. This study has important implications for magneto-hydro-dynamic flow control and propulsion applications.

  Magnetic Field Effects on Axis-Switching and Instabilities in Rectangular Plasma Jets

  Chicatelli

  Amy K.

  NASA

  NASA TM 106090

  Mar. 1993 (Limited Distribution).

  Reduced Order Linear Modeling of Supersonic Compression & Propulsion System Dynamics

  Development of a Three-Dimensional Spectral Lattice Boltzmann Solver

  Dr. Noemi V. Mendoza Diaz

  Dr. Tanya Dugat Wickliff

  First-Year Engineering Students’ Perceptions of their Abilities to Succeed

  This paper presents the results of a computational fluid dynamic model of a supersonic through-flow fan (STF) in supersonic surge. The phenomenon of surge is well known for subsonic turbomachinery. However

  for supersonic turbomachinery like the STF

  a special type of supersonic surge occurs in which a shock oscillates through the fan

  alternating locations between upstream and downstream of the fan. It is also possible for a shock to remain in a fan stage. This analysis focuses on the development of supersonic surge resulting from overpressuring the fan. A model of the STF was constructed around its steady-state experimental performance map using an existing unsteady

  quasi-one-dimensional

  inviscid

  compressible flow code. An exit boundary condition was specified for the overpressuring that forces the shock to move upstream and interfere with normal fan operation. The effects of that interference

  including a shock oscillating across the fan

  are discussed.

  Unsteady Quasi-One-Dimensional Nonlinear Dynamic Model of Supersonic Through-Flow Fan Surge

  Sharath S. Girimaji

  Two lattice Boltzmann method (LBM) formulations are possible to account for the effect of the magnetic field on the velocity field in magnetohydrodynamic (MHD) flows. In the body-force formulation (BFF)

  the magnetic field effects manifest as an external acceleration. In the extended equilibrium formulation (EEF)

  the effect appears through a modified equilibrium distribution function. Further

  for the velocity field itself

  the available choices are the single-relaxation time (SRT) and multi-relaxation time (MRT) models. Thus

  for MHD-LBM

  there are four possible permutations: SRT-BFF

  SRT-EEF

  MRT-BFF and MRT-EEF. Numerical implementation of the first three have already been presented in the literature. In this work

  we

  (i) develop the numerical implementation of MRT-EEF and (ii) perform an assessment of the four possible approaches. Our results indicate that the MRT-EEF is the most robust and accurate of the MHD-LBM computational schemes examined.

  Assessment of Magnetohydrodynamic Lattice Boltzmann Schemes in Turbulence and Rectangular Jets

  Lagoudas

  Dimitris

  Das

  Kaushik

  Shryock

  Kristi

  Oehler

  Stephen

  Recently

  aerospace engineering faculty members and graduate students at the Institution developed a project involving smart materials and implemented it in a freshman-level engineering class to excite first-year students about aerospace material science applications. This project involving aerospace smart material applications addresses curriculum challenges that hinder students' ability to relate math and science concepts to the engineering design process. Shape memory alloys (SMAs)

  the specific type of smart material used in this project

  provide the opportunity for explaining important engineering principles

  such as energy conversion and mechanism actuation

  framed within the subject of mechanics of materials. By introducing projects using SMAs

  students learn about their applications

  their relation to the aerospace field

  and the potential for material science as a future research goal. This paper will present specifications for the project developed involving SMAs

  provide details on the implementation

  and summarize its results.

  Bringing Smart Materials Applications into a Project-Based First-Year Engineering Course

  Samuel P. Bowen

  A two-dimensional cylindrical shear-flow wave theory for the generation of microseisms and infrasound by hurricanes and cyclones is developed as a linearized theory paralleling the seminal work by Longuet-Higgins which was limited to one-dimensional plane waves. Both theories are based on Bernoulli’s principle. A little appreciated consequence of the Bernoulli principle is that surface gravity waves induce a time dependent pressure on the sea floor through a vertical column of water. A significant difference exists between microseisms detected at the bottom of each column and seismic signals radiated into the crust through coherence over a region of the sea floor. The dominant measured frequency of radiated microseisms is matched by this new theory for seismic data gathered at the Fordham Seismic Station both for a hurricane and a mid-latitude cyclone in 1998. Implications for Bernoulli’s principle and this cylindrical stress flow theory on observations in the literature are also discussed.

  Microseism and infrasound generation by cyclones

  Wu

  Xingfu

  Taylor

  Valerie E.

  Garrick

  Shane

  Yu

  Dazhi

  The Lattice Boltzmann method is widely used in simulating fluid flows. In this paper

  we present the performance analysis

  modeling and prediction of a parallel multiblock Lattice Boltzmann application on up to 512 processors on three SMP clusters: two IBM SP systems at San Diego Supercomputing Center (DataStar - p655 and p690) and one IBM SP system at the DOE National Energy Research Scientific Computing Center (Seaborg) using the Prophesy system. By characterizing the performance of the Lattice Boltzmann application as the problem size and the number of processors increase

  we can identify and eliminate performance bottlenecks

  and predict the application performance. The experimental results indicate that the application with large problem sizes scales well across these three clusters

  and performance models using the coupling method are accurate with less than 4.8% average relative prediction error

  Performance Analysis

  Modeling and Prediction of a Parallel Multiblock Lattice Boltzmann Application Using Prophesy System

  Wickliff

  T. D.

  Mendoza Diaz

  N. V.

  Analyzing Enculturation of Diverse Students to the Engineering Practices through FYE Experiences

  Jacques

  Richard

  Argonne National Laboratory

  Texas A&M University