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## Portonovo S. Ayyaswamy

Asa Whitney Professor of Dynamical Engineering

Phone: 215.898.8362
Email: ayya@seas.upenn.edu
Office: 231 Towne Building

### EDUCATION:

Ph.D. (1971) University of California, Los Angeles
Thesis Title: "Natural Convection Flows in Tilted Configurations"

M.E. (1967) Columbia University, New York
Thesis Title: "A Step by Step Design for Helical Tube Multi-Start Coil Heat Transfer Equipment: Entering Tube Side Fluid in the Super Critical Region or Otherwise"
Advisor: Professor Harold G. Elrod., Jr.

M.S. (1965) Columbia University, New York

B.E. (1962) University of Mysore

### COURSES TAUGHT DURING 2011-2012:

MEAM 570. Transport Processes I.  Co/Prerequisite(s): ENM 510 or equivalent, ENM 511 (recommended) or equivalent.
Transport coefficients, Molecular Interpretation of Transport coefficients, Detailed derivations of Conservation Equations for mass, species, momentum and energy, Conduction and Diffusion problems; Finite Fourier Transform Method, Laplace Transforms, Green's function technique; Unidirectional and nearly unidirectional flow and transport; Creeping flow and transport; Laminar flow at High Reynolds number and Transport: Confined flows, unconfined flows; Buoyancy-driven flow: Rayleigh-Benard problem, vertical flat plate problem; Introduction to turbulent flow and transfer.

ENM 251. Analytical Methods for Engineering.  Prerequisite(s): MATH 240 or equivalent along with sophomore standing in SEAS, or permission of instructor(s).

This course introduces students to physical models and mathematical methods that are widely encountered in various branches of engineering. Illustrative examples are used to motivate mathematical topics including ordinary and partial differential equations, Fourier analysis, eigenvalue problems, and stability analysis. Analytical techniques that yield exact solutions to problems are developed when possible, but in many cases, numerical calculations are employed using programs such as Matlab and Maple. Students will learn the importance of mathematics in engineering.

ENM 511. Engineering Mathematics II. (B) Prerequisite(s): ENM 510 or equivalent.

Vector Analysis:  space curves, Frenet – Serret formulae, vector theorems, reciprocal systems, co and contra variant components, orthogonal curvilinear systems. Matrix theory: Gauss-Jordan elimination, eigen values and eigen vectors, quadratic and canonical forms, vector spaces,  linear independence, Triangle and Schwarz inequalities, n-tuple space.Variational calculus: Euler-Lagrange equation, Finite elements, Weak formulation , Galerkin technique, FEMLAB. Tensors: Einstein summation, tensors of arbitrary order, dyads and polyads, outer and inner products, quotient law, metric tensor, Euclidean and Riemannian spaces, physical components, covariant differentiation, detailed evaluation of Christoffel symbols, Ricci’s theorem, intrinsic differentiation, generalized acceleration, Geodesics.

### POSITIONS HELD:

Asa Whitney Professor of Dynamical Engineering 1996-Present
Professor 1987-Present

### CURRENT RESEARCH PROJECTS:

• Targeted Drug Delivery: Multiple Scale Modelling
• Arterial Gas Embolism: Modeling and Experimentation
• Phase Change Transport Phenomena
• Numerical Modelling of Non-Newtonian and Multi-Phase Fluid Flows
• Plasma Arc Heat Transfer
• Cell Culturing in Simulated Microgravity Conditions

### SOME SELECTED PUBLICATIONS:

BOOKS: (See full CV for detailed listing)

"Transport Phenomena with Drops and Bubbles" (with S.S. Sadhal and J.N. Chung), Springer-Verlag, Inc., NY (1997).

"Introduction to Biofluid Mechanics," Chapter 17 in Fluid Mechanics, P.K. Kundu and I.M. Cohen, Academic Press, MA, (2007).

PAPERS: (See full CV for detailed listing)

“Motion of a nano-spheroid in a cylindrical vessel flow: Brownian and hydrodynamic interactions” (with N. Ramakrishnan, Y. Wang, D.M. Eckmann and R. Radhakrishnan), J. Fluid Mech., In Press, (2017).

“Computational models for nanoscale fluid dynamics and transport inspired by non-equilibrium thermodynamics” (with R. Radhakrishnan, H.-Y.Yu, and D.M. Eckmann), Vol. 139, 033001- 033009, ASME J. Heat Transfer, (2017).

“Effect of wall-mediated hydrodynamic fluctuations on the kinetics of a Brownian nano particle, ” (with H.-Y. Yu, D.M. Eckmann, and R. Radhakrishnan), Proc.Roy.Soc. A, 472: 20160397 (2016), (supp info: https://dxdoi.org/10.6084/m9.figshare.c.3590399)

“Nanoparticle stochastic motion in the inertial regime and hydrodynamic interactions close to a cylindrical wall” (with H. Vitoshkin, H.-Y. Yu, D.M. Eckmann, and R. Radhakrishnan), Physical Review Fluids, 1, 054104-1-12, (2016).

“Hydrodynamic interactions of deformable nanocarriers and effect of cross linking” (with A. Sarkar, D.M. Eckmann, and R. Radhakrishnan), Soft Matter, 11, 5955-69, (2015).

“Composite Generalized Langevin Equation for Brownian Motion in Different Hydrodynamic and Adhesion Regimes” (with H.Yu, D.M.Eckmann, and R. Radhakrishnan), Physical Review E, 91:052303-1 – 052303-11 (2015).

“Review of Evaluation Methodologies for Satellite Exterior Materials in Low Earth Orbit (LEO)”(with D. Angirasa) , Journal of Spacecraft and Rockets,  51 (3), 750-761 (2014).

“Temporal Multiscale Approach for Nanocarrier Motion with Simultaneous Adhesion and Hydrodynamic Interactions in Targeted Drug Delivery” (with R.Radhakrishnan, B.Uma, J.Liu, and D.M.Eckmann) , Journal of Computational Physics, 244, 252-263, (2013).

“A hybrid formalism combining fluctuating hydrodynamics and generalized Langevin dynamics for the simulation of nanoparticle thermal motion in an incompressible fluid medium” (with B.Uma, D.M.Eckmann, and R.Radhakrishnan), Molecular Physics, 110 : 1057-1067 (2012).

“Nanoparticle Brownian motion and hydrodynamic interactions in the presence of flow fields” (with U. Balakrishnan, R. Radhakrishnan, T. Swaminathan and D.M. Eckmann), Phys. Fluids, 23, 073602-1-15 (2011).

“Multivalent binding of nanocarrier to endothelial cells under shear flow” (with J. Liu, N. Agrawal, A.J. Calderon, D.M. Eckmann and R. Radhakrishnan), Biophys. J., 101, 319-326 (2011).

“Computational model for nanocarrier binding to endothelium validated using in vivo, in vitro, and atomic force microscopy experiments” (with J. Liu, G.E.R. Weller, B.Zern, D.M. Eckmann, V.R. Muzykanotv and R. Radhakrishnan), Proc. Natl. Acad. Sci. USA,107(38), 16530-16535 (2010).

"Imaging Macromolecular Interactions at an Interface” (with J. Lampe, L. Zhengzheng, I. Dmochowski and D.M. Eckmann), Langmuir, 26 (4), 2452-2459 (2010).

"Effect of a soluble surfactant on a finite-sized bubble motion in a blood vessel” (with T.N. Swaminathan, K. Mukundakrishnan and D.M. Eckmann), Journal of Fluid Mechanics, 642, 509-539 (2010).

"Finite-sized gas bubble motion in a blood vessel: non-Newtonian effects" (with K. Mukundakrishnan and D.M. Eckmann), Physical Review E, 78:036303 (2008).

"The dynamics of two spherical particles in a confined rotating flow: Pedaling motion" (with K. Mukundakrishnan and H. Hu), Journal of Fluid Mechanics, 599, 169-204 (2008).

"Numerical study of wall effects on buoyant gas-bubble rise in a liquid-filled finite cylinder" (with K. Mukundakrishnan, S. Quan and D.M. Eckmann), Physical Review E, 76: 036308 (2007).

“A Front Tracking Method for a Deformable Intravascular Bubble in a Tube with Soluble Surfactant” (with J. Zhang and D.M. Eckmann), J. Computational Physics, 214,366-396 (2006).

“Ground based Studies with a Loop Heat Pipe (LHP) for Spacecraft Thermal Control:  Part II: Experiments under Ambient Conditions” (with M. Parker and B. Drolen), J. Thermophysics and Heat Transfer, 19, 2, 129-136 (2005).

“Ground based Studies with a Loop Heat Pipe (LHP) for Spacecraft Thermal Control:  Part I:  Vacuum Chamber Tests” (with M. Parker and B. Drolen), J. Thermophysics and Heat Transfer, 18, (4), 417-429 (2004).