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Satish Karra
Systems Modeling IRP Leader

Satish Karra is a computational scientist with the Systems Modeling and Computational Science team. He joined EMSL in 2022 as the lead scientist for the Systems Modeling Integrated Research Platform. In this role, he oversees the computational resource needs of EMSL users and advises on simulation and computational strategies to achieve their science objectives. He co-leads road mapping for EMSL's computing and modeling vision.

Satish has 15 years of experience developing scientific software products (high-performance computing, machine learning) for various DOE and private sponsors. Satish’s research is at the interface of engineering, geoscience, applied mathematics, and computing, to solve real-world problems in energy and environmental sciences. He is an expert in building coupled multi-physics and multi-scale models for subsurface applications. His recent works build reduced-order approaches using machine learning and graph-based techniques that emulate physics towards faster decision-making. He also develops methods to link models and experimental data via machine learning. He has 75+ peer-reviewed journal papers and book chapters and is a reviewer for a broad range of journals in computational science, geoscience, flow and transport, and mechanics. He is a developer of the massively parallel code PFLOTRAN and led the parallelization effort in the R&D100 award-winning suite dfnWorks. Satish has mentored 20 students and postdocs. Before joining EMSL, Satish was the team leader for the Subsurface Flow and Transport Team at LANL. At LANL, he led and contributed to projects in the areas of energy, global security, and nuclear security.

## Research Interests

- Porous media modeling
- Reduced-order modeling
- Multi-physics and multi-scale coupling
- Physics-informed machine learning

## Education

- PhD in Mechanical Engineering, Texas A&M University (2011)
- MS in Mechanical Engineering, Texas A&M University (2007)
- BTech in Mechanical Engineering, Indian Institute of Technology Madras (2005)

## Awards and Recognition

- LANL SPOT awards for team leadership and positive influence on co-workers, 2020, 2021.
- Distinguished Performance Award (Subsurface Hydrology, Geology, and Geochemistry Science Team), Los Alamos National Laboratory, 2019.
- Los Alamos Awards Program award for Publication, Los Alamos National Laboratory, 2017 & 2019.
- Distinguished Performance Award (dfnWorks Team), Los Alamos National Laboratory, 2018.
- R&D100 Award for dfnWorks, 2017.
- Federal Laboratory Consortium for Technology Transfer Notable Technology Development Award for dfnWorks Software Suite, 2017.
- Los Alamos Awards Program award for Outstanding Performance in Prototyping Three-dimensional Calculations and Visualizing of Gas Migration in Fractures Following a Subsurface Explosion, Los Alamos National Laboratory, 2016.
- Los Alamos LDRD Early Career Award, Los Alamos National Laboratory, 2014.
- Outstanding Graduate Student Teaching Award, Texas A&M University, 2010.
- Mechanical Engineering Graduate Fellowship, Texas A&M University, 2005-06.
- ‘Graduate Pool’ Fellowship, Texas A&M University, 2005-06.

## Patents

- S. Karra, H. S. Viswanathan, M. K. Mudunuru, V. K. Chillara, and D. N. Sinha. Multi-frequency electrical impedance tomography, Apr. 5 2022. US Patent 11,293,279
- V. K. Chillara, M. K. Mudunuru, H. S. Viswanathan, S. Karra, B. Ahmmed, J. F. App, and G. M. Hoversten. Characterization of fluid inside pipe using multi frequency electrical signal, Apr. 7 2022. US Patent App. 16/948,851
- M. K. Mudunuru, V. K. Chillara, B. Ahmmed, S. Karra, H. S. Viswanathan, J. F. App, G. M. Hoversten, C. J. Champeaux, J. Barraza, et al. Downhole electrode placement optimization, June 9 2022. US Patent App. 17/116,163

## Publications

### 2022

N. Ray, T. Banerjee, B. Nadiga, and S. Karra. "On the viability of quantum annealers to solve fluid flows." *Frontiers in Mechanical Engineering*, 8, 2022

A. J., A. Adedoyin, J. Ambrosiano, P. Anisimov, W. Casper, G. Chennupati, C. Coffrin, H. Djidjev, D. Gunter, S. Karra, N. Lemons, S. Lin, A. Malyzhenkov, D. Mascarenas, S. Mniszewski, B. Nadiga, D. O’malley, D. Oyen, S. Pakin, L. Prasad, R. Roberts, P. Romero, N. Santhi, N. Sinitsyn, P. J. Swart, J. G. Wendelberger, B. Yoon, R. Zamora, W. Zhu, S. Eidenbenz, A. Bärtschi, P. J. Coles, M. Vuffray, and A. Y. Lokhov. "Quantum algorithm implementations for beginners. ACM Transactions on Quantum Computing", 3(4):1–92, Dec 2022

### 2021

H. S. Viswanathan, J. Ajo-Franklin, J. Birkholzer, J. W. Carey, Y. Guglielmi, J. Hyman, S. Karra, L. Pyrak-Nolte, H. Rajaram, G. Srinivasan, et al. "From fluid flow to coupled processes in fractured rock: recent advances and new frontiers." *Reviews of Geophysics*, page e2021RG000744, 2022 2021

S. Srinivasan, D. O’Malley,M.Mudunuru,M. Sweeney, J. Hyman, S. Karra, L. Frash, J. Carey,M. Gross, G. Guthrie, T. Carr, L. Li, and H. Viswanathan. A machine learning framework for rapid forecasting and history matching in unconventional reservoirs. S*cientific Reports*, 11(1), 2021

H. Ushijima-Mwesigwa, J. D. Hyman, A. Hagberg, I. Safro, S. Karra, C. W. Gable, M. R. Sweeney, and G. Srinivasan. "Multilevel graph partitioning for three-dimensional discrete fracture network flow simulations." *Mathematical Geosciences*, pages 1–26, 2021

Ahmmed, S. Karra, V. V. Vesselinov, and M. K. Mudunuru. "Machine learning to discover mineral trapping signatures due to CO2 injection." *International Journal of Greenhouse Gas Control*, 109:103382, 2021

Ahmmed, M. Mudunuru, S. Karra, S. James, and V. Vesselinov. "A comparative study of machine learning models for predicting the state of reactive mixing." *Journal of Computational Physics*, page 110147, 2021

### 2020

B. Ahmmed, M. K. Mudunuru, S. Karra, S. C. James, H. Viswanathan, and J. A. Dunbar. PFLOTRAN-SIP: A PFLO-TRAN module for simulating spectral-induced polarization of electrical impedance data. Energies, 13(24):6552, 2020

S. Srinivasan, D. O’Malley, J. D. Hyman, S. Karra, H. S. Viswanathan, and G. Srinivasan. Transient flow modeling in fractured media using graphs. Physical Review E, 102:052310, Nov 2020

N. Makedonska, S. Karra, H. S. Viswanathan, and G. Guthrie. Role of interaction between hydraulic and natural fractures on production. Journal of Natural Gas Science and Engineering, 82:103451, 2020

N. Lubbers, A. Agarwal, Y. Chen, S. Son, M.Mehana, Q. Kang, S. Karra, C. Junghans, T. C. Germann, and H. S. Viswanathan. Modeling and scale-bridging using machine learning: nanoconfinement effects in porous media. Scientific Reports, 10(1):1–13, 2020

S. Dana, S. Srinivasan, S. Karra, N. Makedonska, J. D. Hyman, D. O’Malley, H. Viswanathan, and G. Srinivasan. Towards real-time forecasting of natural gas production by harnessing graph theory for stochastic discrete fracture networks. Journal of Petroleum Science and Engineering, 195:107791, 2020

V. Romano, S. Bigi, F. Carnevale, J. D. Hyman, S. Karra, A. J. Valocchi, M. C. Tartarello, and M. Battaglia. Hydraulic characterization of a fault zone from fracture distribution. Journal of Structural Geology, page 104036, 2020

D. Osthus, J. D. Hyman, S. Karra, N. Panda, and G. Srinivasan. A probabilistic clustering approach for identifying primary subnetworks of discrete fracture networks with quantified uncertainty. SIAM/ASA Journal on Uncertainty Quantification, 8(2):573–600, 2020

M. Sweeney, C. Gable, S. Karra, P. Stauffer, R. Pawar, and J. D. Hyman. Upscaled discrete fracture matrix model (UDFM): an octree-refined continuum representation of fractured porous media. Computational Geosciences, 24:293–310, 2020

M. Schoenball, J. Ajo-Franklin, D. Blankenship, C. Chai, A. Chakravarty, P. Dobson, C. Hopp, T. Kneafsey, H. Knox,

M. Maceira, M. Robertson, P. Sprinkle, C. Strickland, D. Templeton, P. Schwering, C. Ulrich, T. Wood, J. Ajo-Franklin,T. Baumgartner, K. Beckers, D. Blankenship, A. Bonneville, L. Boyd, S. Brown, J. Burghardt, C. Chai, A. Chakravarty, T. Chen, Y. Chen, B. Chi, K. Condon, P. Cook, D. Crandall, P. Dobson, T. Doe, C. Doughty, D. Elsworth, J. Feldman, Z. Feng, A. Foris, L. Frash, Z. Frone, P. Fu, K. Gao, A. Ghassemi, Y. Guglielmi, B. Haimson, A. Hawkins, J. Heise, C. Hopp, M. Horn, R. Horne, J. Horner, M. Hu, H. Huang, L. Huang, K. Im, M. Ingraham, E. Jafarov, R. Jayne, T. Johnson, S. John-son, B. Johnston, S. Karra, K. Kim, D. King, T. Kneafsey, H. Knox, J. Knox, D. Kumar, K. Kutun, M. Lee, K. Li, Z. Li, M. Maceira, P. Mackey, N. Makedonska, C. Marone, E. Mattson, M. McClure, J. McLennan, T. McLing, C. Medler, R. Mel-lors, E. Metcalfe, J. Miskimins, J. Moore, C. Morency, J. Morris, T. Myers, S. Nakagawa, G. Neupane, G. Newman, A. Nieto, T. Paronish, R. Pawar, P. Petrov, B. Pietzyk, R. Podgorney, Y. Polsky, J. Pope, S. Porse, J. Primo, C. Reimers, B. Roberts,M. Robertson, V. Rodriguez-Tribaldos, W. Roggenthen, J. Rutqvist, D. Rynders, M. Schoenball, P. Schwering, V. Sesetty, C. Sherman, A. Singh, M. Smith, H. Sone, E. Sonnenthal, F. Soom, D. Sprinkle, S. Sprinkle, C. Strickland, J. Su, D. Temple-ton, J. Thomle, C. Ulrich, N. Uzunlar, A. Vachaparampil, C. Valladao, W. Vandermeer, G. Vandine, D. Vardiman, V. Ver-meul, J. Wagoner, H. Wang, J. Weers, N. Welch, J. White, M. White, P. Winterfeld, T. Wood, S. Workman, H. Wu, Y. Wu, E. Yildirim, Y. Zhang, Y. Zhang, Q. Zhou, and M. Zoback. Creation of a mixed-mode fracture network at mesoscale through hydraulic fracturing and shear stimulation. Journal of Geophysical Research: Solid Earth, 125(12), 2020

### 2019

J. D. Hyman, H. Rajaram, S. Srinivasan, N. Makedonska, S. Karra, H. Viswanathan, and G. Srinivasan. Matrix diffusion

in fractured media: New insights into power law scaling of breakthrough curves. Geophysical Research Letters, 46(23):13785–13795, 2019

M. K. Mudunuru, N. Panda, S. Karra, G. Srinivasan, V. T. Chau, E. Rougier, A. Hunter, and H. S. Viswanathan. Surrogate models for estimating failure in brittle and quasi-brittle materials. Applied Sciences, 9(13):2706, 2019

A. Iraola, P. Trinchero, S. Karra, and J. Molinero. Assessing dual continuum method for multicomponent reactive transport. Computers & Geosciences, 130:11–19, 2019

V. Vesselinov, M. Mudunuru, S. Karra, D. O’Malley, and B. Alexandrov. Unsupervised machine learning based on non-negative tensor factorization for analyzing reactive-mixing. Journal of Computational Physics, 395:85–104, 2019

S. Srinivasan, S. Karra, J. Hyman, H. Viswanathan, and G. Srinivasan. Model reduction for fractured porous media: a machine learning approach for identifying main flow pathways. Computational Geosciences, 23(3):617–629, 2019

B. Yuan, Y. J. Tan, M. K. Mudunuru, O. E. Marcillo, A. A. Delorey, P. M. Roberts, J. D. Webster, C. N. Gammans, S. Karra,

G.D. Guthrie, and P. A. Johnson. Using machine learning to discern eruption in noisy environments: A case study using CO2-driven cold-water geyser in Chimayó, New Mexico. Seismological Research Letters, 90(2A):591–603, 2019

A. Hunter, B. A. Moore, M. Mudunuru, V. Chau, R. Tchoua, C. Nyshadham, S. Karra, D. O’Malley, E. Rougier, H. Viswanathan, et al. Reduced-order modeling through machine learning and graph-theoretic approaches for brittle fracture applications. Computational Materials Science, 157:87–98, 2019

S. Rahimi-Aghdam, V.-T. Chau, H. Lee, H. Nguyen, W. Li, S. Karra, E. Rougier, H. Viswanathan, G. Srinivasan, and Z. P. Bažant. Branching of hydraulic cracks enabling permeability of gas or oil shale with closed natural fractures. Proceedings of the National Academy of Sciences, 116(5):1532–1537, 2019

### 2018

H. S. Viswanathan, J. D. Hyman, S. Karra, D. O’Malley, S. Srinivasan, A. Hagberg, and G. Srinivasan. Advancing graph-based algorithms for predicting flow and transport in fractured rock. Water Resources Research, 54(9):6085–6099, 2018

S. Srinivasan, J. Hyman, S. Karra, D. O’Malley, H. Viswanathan, and G. Srinivasan. Robust system size reduction of discrete fracture networks: a multi-fidelity method that preserves transport characteristics. Computational Geosciences, 22(6):1515–1526, 2018

J. Riffault, D. Dempsey, S. Karra, and R. Archer. Microseismicity cloud can be substantially larger than the associated stimulated fracture volume: the case of the Paralana enhanced geothermal system. Journal of Geophysical Research: Solid Earth, 123(8):6845–6870, 2018

G. Srinivasan, J. D. Hyman, D. A. Osthus, B. A. Moore, D. O’Malley, S. Karra, E. Rougier, A. A. Hagberg, A. Hunter, and H. S. Viswanathan. Quantifying topological uncertainty in fractured systems using graph theory and machine learning. Scientific Reports, 8(1):11665, 2018

D. R. Harp, J. P. Ortiz, S. Pandey, S. Karra, D. Anderson, C. Bradley, H. Viswanathan, and P. H. Stauffer. Immobile pore-water storage enhancement and retardation of gas transport in fractured rock. Transport in Porous Media, 124(2):369–394, Sep 2018

D. O’Malley, S. Karra, J. D. Hyman, H. S. Viswanathan, and G. Srinivasan. Efficient Monte Carlo with graph-based sub-surface flow and transport models. Water Resources Research, 54(5):3758–3766

A. E. Lovell, S. Srinivasan, S. Karra, D. O’Malley, N. Makedonska, H. S. Viswanathan, G. Srinivasan, J. W. Carey, and

L.P. Frash. Extracting hydrocarbon from shale: An investigation of the factors that influence the decline and the tail of the production curve. Water Resources Research, 54(5):3748–3757

G. D. Guthrie, R. J. Pawar, J. W. Carey, S. Karra, D. R. Harp, and H. S. Viswanathan. The mechanisms, dynamics, and implications of self-sealing and CO2 resistance in wellbore cements. International Journal of Greenhouse Gas Control, 75:162–179, 2018

S. Karra, D. O’Malley, J. Hyman, H. Viswanathan, and G. Srinivasan. Modeling flow and transport in fracture networks using graphs. Physical Review E, 97(3):033304, 2018

D. T. Birdsell, S. Karra, and H. Rajaram. On the representation of the porosity-pressure relationship in general subsurface flow codes. Water Resources Research, 54, 2018

J. D. Hyman, S. Karra, J. W. Carey, C. W. Gable, H. Viswanathan, E. Rougier, and Z. Lei. Discontinuities in effective permeability due to fracture percolation. Mechanics of Materials, 119:25–33, 2018

### 2017

M. K. Mudunuru, V. K. Chillara, S. Karra, and D. Sinha. Scalable time-series feature engineering framework to understand multiphase flow using acoustic signals. In Proceedings of Meetings on Acoustics ICU, volume 32, page 055003. Acoustical Society of America, 2017

M. Mudunuru, S. Karra, D. Harp, G. Guthrie, and H. Viswanathan. Regression-based reduced-order models to predict transient thermal output for enhanced geothermal systems. Geothermics, 70:192–205, 2017

S. K. Hansen, S. Pandey, S. Karra, and V. V. Vesselinov. CHROTRAN 1.0: A mathematical and computational model for in situ heavy metal remediation in heterogeneous aquifers. Geoscientific Model Development, 10(12):4525–4538, 2017

T. Hadgu, S. Karra, E. Kalinina, N. Makedonska, J. D. Hyman, K. Klise, H. S. Viswanathan, and Y. Wang. A comparative study of discrete fracture network and equivalent continuum models for simulating flow and transport in the far field of a hypothetical nuclear waste repository in crystalline host rock. Journal of Hydrology, 553:59–70, 2017

H. Djidjev, D. O’Malley, H. Viswanathan, J. Hyman, S. Karra, and G. Srinivasan. Learning on graphs for predictions of frac-ture propagation, flow and transport. In 2017 IEEE International Parallel and Distributed Processing Symposium Workshops (IPDPSW), pages 1532–1539, May 2017

M. K. Mudunuru, S. Karra, N. Makedonska, and T. Chen. Sequential geophysical and flow inversion to characterize fracture networks in subsurface systems. Statistical Analysis and Data Mining: The ASA Data Science Journal, 10,(5):326–342, 2017

J. Chang, S. Karra, and K. B. Nakshatrala. Large-scale optimization-based non-negative computational framework for dif-fusion equations: Parallel implementation and performance studies. Journal of Scientific Computing, 70(1):243–271, 2017

### 2016

S. K. Hansen, B. Berkowitz, V. V. Vesselinov, D. O’Malley, and S. Karra. Push-pull tracer tests: Their information content and use for characterizing non-fickian, mobile-immobile behavior. Water Resources Research, 52(12):9565–9585, 2016

N. Makedonska, J. D. Hyman, S. Karra, S. L. Painter, C. W. Gable, and H. S. Viswanathan. Evaluating the effect of internal aperture variability on transport in kilometer scale discrete fracture networks. Advances in Water Resources, 94:486–497, 2016

G. Aldrich, J. D. Hyman, S. Karra, C. W. Gable, N. Makedonska, H. S. Viswanathan, J. Woodring, and B. Hamann. Anal-ysis and visualization of discrete fracture networks using a flow topology graph. IEEE Transactions on Visualization and Computer Graphics, doi: 10.1109/TVCG.2016.2582174, 2016

J. D. Hyman, G. Aldrich, H. S. Viswanathan, N. Makedonska, and S. Karra. Fracture length and transmissivity correlations: Implications for transport simulations in discrete fracture networks. Water Resources Research, 52(8):6472–6489, 2016

J. D. Hyman, J. Jiménez-Martínez, H. S. Viswanathan, J. W. Carey, M. L. Porter, E. Rougier, S. Karra, Q. Kang, L. Frash,

L. Chen, Z. Lei, D. O’Malley, and N. Makedonska. Understanding hydraulic fracturing: A multi-scale problem. Philosophical Transactions A, 374(2078), 2016

M. Grasinger, D. O’Malley, V. Vesselinov, and S. Karra. Decision analysis for robust CO2 injection: Application of bayesian-information-gap decision theory. International Journal of Greenhouse Gas Control, 49:73–80, 2016

### 2015

D. O’Malley, S. Karra, R. P. Currier, N. Makedonska, J. D. Hyman, and H. S. Viswanathan. Where does water go during hydraulic fracturing? Groundwater, 54(4):488–497, 2015

R. S. Middleton, J. W. Carey, R. P. Currier, J. D. Hyman, Q. Kang, S. Karra, J. Jiménez-Martínez, M. L. Porter, and H. S. Viswanathan. Shale gas and non-aqueous fracturing fluids: Opportunities and challenges for supercritical CO2. Applied Energy, 147(0):500 – 509, 2015

N. Makedonska, S. L. Painter, Q. M. Bui, C. W. Gable, and S. Karra. Particle tracking approach for transport in three-dimensional discrete fracture networks. Computational Geosciences, 19(5):1123–1137, 2015

J. D. Hyman, S. L. Painter, H. S. Viswanathan, N. Makedonska, and S. Karra. Influence of injection mode on transport properties in kilometer-scale three-dimensional discrete fracture networks. Water Resources Research, 51(9):7289–7308, 2015

S. Srinivasan and S. Karra. Flow of “stress power-law” fluids between parallel rotating discs with distinct axes. International Journal of Non-Linear Mechanics, 74(0):73 – 83, 2015

S. Karra, N. Makedonska, H. S. Viswanathan, S. L. Painter, and J. D. Hyman. Effect of advective flow in fractures and matrix diffusion on natural gas production. Water Resources Research, 51(10):8646–8657, 2015

J. D. Hyman, S. Karra, N. Makedonska, C. W. Gable, S. L. Painter, and H. S. Viswanathan. dfnworks: A discrete fracture network framework for modeling subsurface flow and transport. Computers & Geosciences, 84:10 – 19, 2015

### 2014

S. Karra, S. L. Painter, and P. C. Lichtner. Three-phase numerical model for subsurface hydrology in permafrost-affected regions (PFLOTRAN-ICE v1.0). The Cryosphere, 8(5):1935–1950, 2014

S. L. Painter and S. Karra. Constitutive model for unfrozen water content in subfreezing unsaturated soils. Vadose Zone Journal, 13(4), 2014

S. Kelkar, K. Lewis, S. Karra, G. Zyvoloski, S. Rapaka, H. S. Viswanathan, P. K. Mishra, S. Chu, D. Coblentz, and R. Pawar. A simulator for modeling coupled thermo-hydro-mechanical processes in subsurface geological media. International Journal of Rock Mechanics and Mining Sciences, 70(0):569 – 580, 2014

### 2013

K. C. Lewis, S. Karra, and S. Kelkar. A model for tracking fronts of stress-induced permeability enhancement. Transport in Porous Media, 99(1):17–35, 2013

S. Karra. Modeling the diffusion of a fluid through viscoelastic polyimides. Mechanics of Materials, 66(0):120 – 133, 2013

### 2012

S. Karra and K. R. Rajagopal. A model for the thermo-oxidative degradation of polyimides. Mechanics of Time-Dependent Materials, 16(3):329–342, 2012

S. Karra and K. R. Rajagopal. Degradation and healing in a generalized neo-hookean solid due to infusion of a fluid. Me-chanics of Time-Dependent Materials, 16(1):85–104, 2012

### 2011

S. Karra, V. Průša, and K. R. Rajagopal. On maxwell fluids with relaxation time and viscosity depending on the pressure. International Journal of Non-Linear Mechanics, 46(6):819 – 827, 2011

S. Karra and K. R. Rajagopal. Modeling the non-linear viscoelastic response of high temperature polyimides. Mechanics of Materials, 43(1):54 – 61, 2011

### 2010

C. Bridges, S. Karra, and K. R. Rajagopal. On modeling the response of the synovial fluid: Unsteady flow of a shear-thinning, chemically-reacting fluid mixture. Computers & Mathematics with Applications, 60(8):2333 – 2349, 2010

### 2009

S. Karra and K. R. Rajagopal. Development of three dimensional constitutive theories based on lower dimensional experi-mental data. Applications of Mathematics, 54(2):147–176, 2009

S. Karra and K. R. Rajagopal. A thermodynamic framework to develop rate-type models for fluids without instantaneous elasticity. Acta Mechanica, 205(1-4):105–119, 2009

S. Karra and A. R. Srinivasa. Simulation of the electrospinning process. International Journal of Applied Mechanics and Engineering, 14(1):175–188, 2009

### 2006

A. Narasimhan and S. Karra. An inverse heat transfer method to provide near-isothermal surface for disc heaters used in microlithography. International Journal of Heat and Mass Transfer, 49(23–24):4624 – 4632, 2006