# Kevin T Clarno

# Kevin T Clarno

### Distinguished R&D Staff; Group Leader, Reactor Physics

### Bio

Dr. Kevin T. Clarno has been employed at Oak Ridge National Laboratory (ORNL) since 2004, and is also an Assistant Professor at the University of Tennessee-Knoxville, as a Joint Faculty in the Nuclear Engineering Department. Dr. Clarno is the Interim Director of the Consortium for Advanced Simulation of LWRs [Light-Water Reactors] (www.casl.gov), which includes directing the research, development, and application of coupled fluid-dynamics, structural mechanics, conjugate heat transfer, and radiation transport for the modeling of commercial nuclear reactors. Dr. Clarno recently served as the lead of the Modernization Team of the SCALE nuclear analysis code suite (scale.ornl.gov), which is transforming a legacy nuclear analysis software package with thousands of users throughout the world to enable advanced algorithms on modern computing platforms.

Dr. Clarno has served as the Principal Investigator for several major ORNL Laboratory-Directed Research and Development (LDRD) and DOE projects, including the development of the a multi-institutional team developing the AMP Nuclear Fuel Performance code built upon a flexible scientific computing foundation for high-performance computing architectures, high-performance computing radiation (Boltzmann) transport codes for nuclear reactor simulation (Denovo) and the integration of the NESTLE core simulator with the SCALE nuclear analysis code system. Dr. Clarno maintains a focus on mentoring the next generation of researchers; he has advised more than 25 students and post-degree researchers. He has served on eight M.S. or Ph.D. committees at four universities and has co-instructed several courses at the University of Tennessee. Dr. Clarno is actively involved in both nuclear fuel and reactor analysis and the development and improvement in ORNL nuclear analysis software using C++ and Fortran. Dr. Clarno has published more than 70 manuscripts in journals, conference proceedings, and technical reports, spanning diverse areas of nuclear science and engineering including cross section processing, isotopic depletion, fuel performance, reactor analysis, thermal-hydraulics, used fuel disposition, and thermo-chemistry.

### Awards

**International Awards**

- R&D Magazine's "R&D 100" Award

**ORNL Laboratory Awards**

- Laboratory Awards Night
- Engineering Technology by a Team Award - Development of Denovo (2010)
- Early Career Engineering Achievement Award - High-Performance Computing for Nuclear Systems (2008)

- Significant Event Awards (SEAs)
- VERA-CS Performance Improvements (2016)
- Fukishima Analysis Support(2011)
- Coupling fuel performance and reactor physics (2010)

- Division-level Awards
- Nuclear Science and Technology Division (NSTD) Technical Excellence (2006)
- NSTD Technical Excellence (2005)

**University Awards**

- Naval Nuclear Propulsion [Rickover] Fellow (2002–2004)
- Institute of Nuclear Power Operations [INPO] Fellow (2000–2001)
- National Academy for Nuclear Training [NANT] Scholar (2000–2001)
- Texas A&M University Regents Fellow (1999–2000)

**Undergraduate Atheletic Awards**

- Academic All-American [New England Region] (1997)
- All-Conference [NEFC] Football (1997-1998)
- MIT Varsity Football Letterman (1995-1998)
- MIT Varsity Lacross Letterman (1998-1999)

### Projects

**Principal Investigator Awards and Roles**

- "CASL CRUD-Induced Power Shift (CIPS) Analysis"
- DOE/SC ASCR Leadership Computing Challenge [ALCC] (2016-2017)
- 75M CPU-hours on leadership-class computing hardware
- With T. Evans, S. Hamilton, T. Pandya, B. Collins, G. Davidson, and A. Godfrey

- Development of the AMP Nuclear Fuel Performance Code
- DOE/NE Office of Advanced Modeling and Simulation (2009-2013)
- With many researchers at ORNL and Los Alamos National Laboratory

- “Understanding Used Nuclear Fuel Cladding Performance Characteristics During Very Long-Term Storage Through Coupled Experiments and Simulations"
- ORNL Laboratory-Directed Research and Development [LDRD] (2011-2013)
- With M. Berrill, S. Gorti, R. Jubin, B. Philip, B. Radhakrishnan, Y. Yong

- “Denovo: The Next-Generation, High-Performance Computing Solver for Multiscale Nuclear Energy Transport”
- ORNL LDRD (2008–2010)
- With K. Evans, T. Evans, M. Williams

- “Development of an Advanced Light Water Reactor Analysis Capability”
- ORNL LDRD (2008–2009)
- With M. Jessee, G. Maldonado, E. Popov

- “Terascale Simulation Tools for Next-Generation Nuclear Energy Systems”
- ORNL LDRD (2005–2007)
- With E. d'Azevedo, A. Khamayseh, V. de Almeida

**Co-Investigator and Collaborator Awards and Roles**

- “Consortium for Advanced Simulation of LWRs (CASL)”
- DOE Energy Innovation Hub, Principal Investigator: D. Kothe (2010-2019)
- With 20 institutions, including Phase 1 and Phase 2

- "Delivering Advanced Modeling & Simulation for Nuclear Energy Applications"
- DOE/SC ASCR Leadership Computing Challenge [ALCC], PI: J. Turner (2015-2016)
- 75M CPU-hours on leadership-class computing hardware
- With B. Collins, T. Evans, and S. Slattery

- "Uncertainty Quantification of Three-Dimensional Reactor Assembly Simulations"
- DOE/SC INCITE Award, PI: T. Evans (2010-2011)
- 8M CPU-hours on leadership-class computing hardware
- With M. Jessee, W. Joubert, S. Mosher, and B. Rearden

- “Advanced Mesh-Enabled Monte Carlo Capability for Multi-Physics Reactor Analysis”
- DOE Nuclear Energy University Program, PI: P. Wilson [UW-Madison] (2008–2011)
- With F. Brown, T. Evans, T. Tautges

- “Burner Reactor Integrated Performance and Safety Code (BRISC)”
- Sandia National Laboratory LDRD, Principal Investigator: R. Schmidt (2006–2009)
- With N. Belcourt, R. Hooper, L. Humphries, A. Lorber, R. Pryor, B. Spotz

- “Development of a Global Advanced Nuclear Fuel Rod Model”
- ORNL LDRD, Principal Investigator: S. Simunovic (2006–2009)
- With T. Besmann, I. Gauld, P. Nukala, L. Ott, R. Stoller, C. Weber

### Publications

S. Stimpson, J. Powers, **K. Clarno**, et al., “Pellet-clad mechanical interaction screening using VERA applied to Watts Bar Unit 1, Cycles 1–3,” *Nuclear Engineering and Design*, **327**, 172–186, 2018.

S. Stimpson, Y. Liu, B. Collins, **K. Clarno**, “A Lumped Parameter Method of Characteristics Approach and Multigroup Kernels Applied to the Subgroup Self-shielding Calculation in MPACT,” *Nuclear Engineering and Technology*, **49**(6), 1240–1249, 2017.

B. Kochunas, B. Collins, S. Stimpson, R. Salko, D. Jabaay, A. Graham, Y. Liu, K. Kim, W. Wieselquist, A. Godfrey, **K. Clarno**, et al, “VERA Core Simulator Methodology for Pressurized Water Reactor Cycle Depletion,” *Nucl. Sci. Eng.*, 185(1), 217–231, 2017.

J. Turner, **K. Clarno**, et al, “The Virtual Environment for Reactor Applications (VERA): Design and architecture,” *Journal of Computational Physics*, **326**, 544–568, 2016.

S. Hamilton, M. Berrill, **K. Clarno**, et al, “An Assessment of Coupling Algorithms for Nuclear Reactor Core Physics Simulations” *Journal of Computational Physics*, **311**, 241–257, 2016.

M. Piro, J. Banfield, **K. Clarno**, et al., Corrigendum to “Coupled thermochemical, isotopic evolution and heat transfer simulations in highly irradiated UO_{2} nuclear fuel,” *J. Nucl. Matl.* **478**, 375–377, 2016.

R. Schmidt, K. Belcourt, R. Hooper, R. Pawlowski, **K. Clarno**, et al, “An Approach for Coupled-Code Multiphysics Core Simulations from a Common Input,” *Annals of Nuclear Energy*, **84**, 140–152, 2015.

B. Philip, M. Berrill, S. Allu, S. Hamilton, R. Sampath, **K. Clarno**, and G. Dilts, “A Parallel Multi-Domain Solution Methodology Applied to Nonlinear Thermal Transport Problems in Nuclear Fuel Pins,” *Journal of Computational Physics*, **286**, 143–171, Apr 2015.

A. Phillippe, **K. Clarno**, et al., “A Validation Study of Pin Heat Transfer for MOX Fuel Based on the IFA-597 Experiments,” *Nucl. Sci. Eng.* **178**(2), 2014.

A. Phillippe, **K. Clarno**, et al., “A Validation Study of Pin Heat Transfer for UO_{2} Fuel Based on the IFA-432 Experiments,” *Nucl. Sci. Eng.* **177**(3), 2014.

M. Piro, J. Banfield, **K. Clarno**, et al., “Coupled thermochemical, isotopic evolution and heat transfer simulations in highly irradiated UO_{2} nuclear fuel,” *J. Nucl. Matl.* **441**, 240–251, 2013.

**K. Clarno** et al., “The AMP (Advanced MultiPhysics) Nuclear Fuel Performance Code,” *Nucl. Eng. Design* **252**(1), 108–120, Nov 2012.

G. Yesilyurt, **K. Clarno**, et al, “C5 Benchmark Problem with Discrete Ordinate Radiation Transport Code Denovo,” *Nucl. Sci. Eng.* **176**(2), 274–283, Nov 2011.

T. Evans, **K. Clarno**, and J. Morel, “A Transport Acceleration Scheme for Multigroup Discrete Ordinates with Upscattering,” *Nucl. Sci. Eng. ***165**(3), 292–304 (2010).

T. Evans, A. S. Stafford, and **K. Clarno**, “Denovo–A New Three-Dimensional Parallel Discrete Ordinates Code in SCALE,” *Nucl. Technol.* **171**(2), 171–200 (2010).

D. Williams and **K. Clarno**, “Evaluation of Salt Coolants for Reactor Applications,” *Nucl. Technol.* **163**(3), 330–343 (2008).

Z. Zhong, **K. Clarno**, T. Downar, and M. DeHart, “Implementation of a Two-Level Coarse Mesh Finite Difference Acceleration of an Arbitrary Geometry Two-Dimensional Discrete-Ordinates Transport Method,” *Nucl. Sci. Eng. ***158**(3), 289–298 (2008).

**K. Clarno** and M. Adams, “Capturing the Effects of Unlike Neighbors in Single-Assembly Calculations,” *Nucl. Sci. Eng. ***149**(2), 182–196 (2005).

**K. Clarno** and Y. Hassan, “Development of a RELAP5-3D Multi-dimensional Model of a VVER‑1000 NPP for Analysis of a LB LOCA,” *Nucl. Technol.* **141**(2), 142–156 (2003).

Technical Reports

S. Stimpson, **K. Clarno**, et al, “Demonstration of Coupled Tiamat Quarter Core Calculations on Watts Bar Unit 1, Cycle 1,” ORNL Report ORNL/SR-2017/463, Sep 2017.

**K. Clarno**, et al, “Software Quality Assurance and Verification for the MPACT Library Generation Process,” ORNL Report ORNL/TM-2017/247, May 2017.

K. Kim, **K. Clarno**, et al, “Development of the V4.2m5 and V5.0m0 Multigroup Cross Section Libraries for MPACT for PWR and BWR,” ORNL Report ORNL/TM-2017/95, Mar 2017.

M. Jessee, D. Wiarda, **K. Clarno**, et al, “Development and Maintenance of SCALE Lattice and Reactor Physics Capabilities,” ORNL Report ORNL/LTR-2016/585, Sep 2016.

S. Stimpson, B. Collins, **K. Clarno**, et al, “MPACT Subgroup Self-Shielding Efficiency Improvements,” ORNL Report ORNL/TM-2016/407, Sep 2016.

T. Downar, et al, “MPACT Theory Manual, Version 2.2.0,” ORNL Report ORNL/TM-2016/476, Aug 2016.

M. Jessee, D. Wiarda, **K. Clarno**, et al, “TRITON: A Multipurpose Transport, Depletion, and Sensitivity and Uncertainty Analysis Module,” ORNL Report ORNL/TM-2016/56, Apr 2016.

S. Stimpson, **K. Clarno**, et al, “Standalone BISON Fuel Performance Results for Watts Bar Unit 1, Cycles 1–3,” ORNL Report ORNL/TM-2015/776, Apr 2016.

M. Williams, “XSPROC: The Cross Section Processing Module for SCALE,” ORNL Report ORNL/TM-2015/721 Apr 2016.

**K. Clarno**, “Determine Operating Reactor to Use for the 2016 PCI Level 1 Milestone,” ORNL Report ORNL/SPR-2016/38, Feb 2016.

**K. Clarno**, et al, “T0002 SCALE Neutronics Updates for Reactor and Spent Fuel Analyses Task 6: SCALE/TRITON Acceleration,” ORNL Report ORNL/LTR-2016/35, Jan 2016.

S. Stimpson, **K. Clarno**, et al, “Executing BISON-CASL Using VERA-CS Output,” ORNL Report ORNL/SPR-2015/609, Dec 2015.

S. Bowman, **K. Clarno**, et al, “SCALE Support for Reactor and Spent Fuel Analyses,” ORNL Report ORNL/SPR-2015/572, Oct 2015.

M. Jessee, U. Mertyurek, **K. Clarno**, S. Bowman, *SCALE Neutronics Updates for Reactor and Spent Fuel Analyses*, ORNL/LTR-2014/517, Oct 2014.

R. Pawlowski, **K. Clarno**, R. Montgomery, *Demonstrate Integrated VERA-CS for the PCI Challenge Problem,* CASL-I-2014-0153-000, Aug 2014.

S. Palmtag, et al, *Demonstration of Neutronics Coupled to Thermal-Hydraulics for a Full-Core Problem using VERA*, CASL-U-2013-0196-000, Dec 2013.

B. Rearden, **K. Clarno**, et al, *Report on Used Nuclear Fuel Characterization Enhancements in SCALE*, ORNL/LTR-2013/425, Oct 2013.

S. Palmtag, et al, *Coupled Single Assembly Solution with VERA (Problem 6)*, CASL-U-2013-0150-000, Jul 2013.

S. Hayes and **K. Clarno**, *Fuels IPSC Software Quality Assurance Plan V1.2.2*, LLNL-TM-493620, Nuclear Energy Advanced Modeling and Simulation (NEAMS) Program, Sep 22, 2011.

A. Phillippe, L. Ott, **K. Clarno**, and J. Banfield, *Analysis of the IFA-432, IFA-597, and IFA-597 MOX Fuel Performance Experiments by FRAPCON-3,4*, ORNL/TM-2012/195, Oak Ridge National Laboratory, Oak Ridge, TN, Aug 2012.

**K. Clarno** and R. Howard, Problem *Specification for FY12 Modeling of Used Nuclear Fuel during Extended Storage*, ORNL/TM-2012/80, Oak Ridge National Laboratory, Oak Ridge, TN, Feb 2012.

**K. Clarno** et al., *Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations*, ORNL/TM-2012/33, Oak Ridge National Laboratory, Oak Ridge, Tenn., Jan 2012.

B. Philip, **K. Clarno**, and W. Cochran, *Software Design Document for the AMP Nuclear Fuel Performance Code*, ORNL/TM-2010/34, Oak Ridge National Laboratory, Oak Ridge, TN, Mar 2010.

R. Schmidt, K. Belcourt, **K. Clarno** et al., *Foundational Development of an Advanced Nuclear Reactor Integrated Safety Code*, SAND2010-0878, Sandia National Laboratories, Albuquerque, NM, 2010.

**K. Clarno** and J. Renier, *Test Problem #3: 2009 Three-Dimensional Boiling Water Reactor Simulations*, ORNL/TM-2009/250, Oak Ridge National Laboratory, Oak Ridge, Tenn., Oct 2009.

T. Evans and **K. Clarno**, *C++ Coding Standards for the AMP Project*, ORNL/TM-2009/240, Oak Ridge National Laboratory, Oak Ridge, TN, Oct 2009.

**K. Clarno**, J. Turner, and G. Hansen, *Roadmap to an Engineering-Scale Nuclear Fuel Performance and Safety Code*, ORNL/TM-2009/233, Oak Ridge National Laboratory, Oak Ridge, TN, Sep 2009.

R. Primm III, **K. Clarno**, et al., *Design Study for a Low-Enriched Uranium Core for the High Flux Isotope Reactor, Annual Report for the FY 2006*, ORNL/TM-2006/136, Oak Ridge National Laboratory, Oak Ridge, TN, Oct 2006.

D. Williams, L. Toth, and **K. Clarno**, *Assessment of Candidate Molten Salt Coolants for the Advanced High Temperature Reactor (AHTR)*, ORNL/TM-2006/12, Oak Ridge National Laboratory, Oak Ridge, TN, Mar 2006.

D. Ingersoll, **K. Clarno**, C. Forsberg, J. Gehin, R. Christensen, C. Davis, G. Hawkes, J. Sterbentz, T. Kim, T. Taiwo, and W. Yang, *Status of Physics and Safety Analyses for the Liquid-Salt–Cooled Very High-Temperature Reactor (LS-VHTR)*, ORNL/TM-2005/218, Oak Ridge National Laboratory, Oak Ridge, TN, Dec 2005.

D. Ingersoll, **K. Clarno** et al., *Trade Studies for the Liquid-Salt-Cooled Very High-Temperature Reactor: Fiscal Year 2006 Progress Report*, ORNL/TM-2006/140, Oak Ridge National Laboratory, Oak Ridge, TN, Feb 2007.

**K. Clarno**, “TXYPL – TXY with General Anisotropic Scattering,” Bechtel Bettis Atomic Power Laboratory Internal Letter, B-MER(ACRE)-59 and Attachment, Jul 2003.

J. Powers, S. Stimpson, **K. Clarno**, et al, “Demonstration of Fully Coupled Multiphysics Simulations for Watts Bar Unit 1,” *Proceedings of the 2017 Water Reactor Fuel Performance Meeting* (WRFPM 2017) Sep 2017.

S. Stimpson, **K. Clarno**, et al., “Effect of Clad Fast Neutron Flux Distribution on Quarter-Core BISON Fuel Performance Calculations,” *2017 Water Reactor Fuel Performance Meeting*, Sep 2017.

K. Kim, M. Williams, D. Wiarda, **K. Clarno**, et al., “Development of the CASL-VERA V4.2m5 MPACT 51-group Libraries for ENDF/B-VII.0 and VII.1,” *M&C International Conference on Mathematics & Computational Methods Applied to Nuclear Science and Engineering*, South Korea, Apr 2017.

S. Stimpson, Y. Liu, B. Collins, **K. Clarno**, “A Multigroup, Lumped Parameter MOC Method for Subgroup Self-Shielding in MPACT,” *M&C International Conference on Mathematics & Computational Methods Applied to Nuclear Science and Engineering*, South Korea, Apr 2017.

S. Stimpson, **K. Clarno**, et al., “Assessing Pellet-Clad Interaction with VERA: WBN1, Cycles 6–7,” *Top Fuel*, Boise, ID, Sep 2016.

B. Collins, R. Salko, S. Stimpson, **K. Clarno**, et al., “Simulation of CRUD Induced Power Shift Using the VERA Core Simulator and MAMBA,” *PHYSOR 2016*, Sun Valley, ID, May 2016.

A. Godfrey, **K. Clarno**, et al., “VERA Benchmarking Results for Watts Bar Nuclear Plant Unit 1 Cycles 1–12,” *PHYSOR 2016*, Sun Valley, ID, May 2016.

S. Stimpson, J. Powers, **K. Clarno**, et al., “Assessment of Pellet-Clad Interaction Indicators in Watts Bar Unit 1, Cycles 1–3 Using VERA,” *PHYSOR 2016*, Sun Valley, ID, May 2016.

B. Rearden, K. Bekar, C. Celik, **K. Clarno**, “Criticality Safety Enhancements for SCALE 6.2 and Beyond,” *ICNC 2015*, Charlotte, NC, Sep 2015.

A. Toth, C. Kelly, S. Slattery, S. Hamilton, **K. Clarno**, and R. Pawlowski, “Analysis of Anderson Acceleration on a Simplified Neutronics/Thermal Hydraulics System,” *Joint International Conference on Mathematics and Computation (M&C 2015), Supercomputing in Nuclear Applications (SNA-2015) and Monte Carlo Methods (MC-2015), *Nashville, TN, Apr 2015.

B. Rearden, R. Lefebvre, J. Lefebvre, **K. Clarno**, et al., “Modernization Strategies for SCALE-6.2,” *Joint International Conference on Mathematics and Computation (M&C 2015), Supercomputing in Nuclear Applications (SNA-2015) and Monte Carlo Methods (MC-2015), *Nashville, TN, Apr 2015.

**K. Clarno**, R. Pawlowski, R. Montgomery, T. Evans, B. Collins, B. Kochunas, D. Gaston, and J. Turner, “High-Fidelity Modeling of Pellet-Clad Interaction using the CASL Virtual Environment for Reactor Analysis” *Joint International Conference on Mathematics and Computation (M&C 2015), Supercomputing in Nuclear Applications (SNA-2015) and Monte Carlo Methods (MC-2015), *Nashville, TN, Apr 2015.

R. Pawlowski, **K. Clarno**, R. Montgomery, R. Salko, T. Evans, J. Turner, and D. Gaston, “Design of a High-Fidelity Core Simulator for Analysis of Pellet-Clad Interaction,”

B. Kochunas, B. Collins, D. Jabaay, S. Stimpson, **K. Clarno**, S. Palmtag, T. Downar, and J. Gehin, “VERA Core Simulator Methodology for PWR Cycle Depletion,”

S. Palmtag, **K. Clarno**, et al., “Coupled Neutronics and Thermal-Hydraulics Solutions of a Full-Core PWR Using VERA-CS,” *PHYSOR 2014 – The Role of Reactor Physics toward a Sustainable Future (PHYSOR-2014), *Kyoto, Japan, Sep 2014.

S. Hamilton, **K. Clarno**, et al., “Multiphysics Simulations for LWR Analyses,” *International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2013), *Sun Valley, ID, May 2013.

J. Hansel, J. Ragusa, S. Allu, M. Berrill, **K. Clarno**, “Analysis of Physics-Based Preconditioning for Single-Phase Subchannel Equations,” *International Conference on Mathematics and Computational Methods Applied to Nuclear Science and Engineering (M&C 2013), *Sun Valley, ID, May 2013.

Y. Yong, et al., “Observation and Mechanism of Hydride in Zircaloy-4 and Local Hydride Re-orientation Induced by High Pressure at High Temperature,” *International High-Level Radioactive Waste Management, Albuquerque*, NM, May 2013.

B. Radhakrishnan, S. Gorti, Y. Yong, **K. Clarno**, “Phase Field Simulations of Hydride Reorientation in Zircaloys,” *International High-Level Radioactive Waste Management, Albuquerque*, NM, May 2013.

S. Hamilton, **K. Clarno**, B. Philip, M. Berrill, R. Sampath, and S. Allu, "Integrated Radiation Transport and Nuclear Fuel Performance for Assembly-Level Simulations," *PHYSOR 2012*—*Advances in Reactor Physics—Linking Research, Industry, and Education*, Knoxville, Tenn., Apr 15–20, 2012, on CD-ROM, American Nuclear Society, LaGrange, Park, IL, 2012.

G. Yesilyurt, **K. Clarno**, I. C. Gauld, and J. D. Galloway, “Modular ORIGEN-S for Multi-Physics Code Systems,” *Proceedings of the Mathematics and Computations Division of the American Nuclear Society Topical Meeting (M&C-2011)*, May 2011.

**K. Clarno**, “Parallel (Sn) Transport Algorithm in NEWTRNX,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR 2008)*, Sep 2008.

S. Vilkomir, W. Swain, J. Poore, and **K. Clarno**, “Modeling Input Space for Testing Scientific Computational Software: A Case Study,” *Proceedings of the International Conference on Computational Science (ICCS-2008)*, Jun 2008.

B. Ganapol, **K. Clarno**, and S. Hamilton, “An Embedded Semi-Analytical Benchmark with Iterative Interpolation for Neutron Transport Methods Verification,” *Proceedings of the Joint Supercomputing in Nuclear Applications and Mathematics and Computations Division of the American Nuclear Society Topical Meeting (SNA/M&C-2007)*, Apr 2007.

M. Williams, J. Gehin, and **K. Clarno**, “Sensitivity Analysis of Reactivity Responses Using One-Dimensional Discrete Ordinates and Three-Dimensional Monte Carlo Methods,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR-2006)*, Sep 2006.

Z. Zhong, T. Downar, M. DeHart, and **K. Clarno**, “Coarse Mesh Finite Difference Acceleration in the Two-Dimensional Discrete Ordinates Transport Calculation,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR 2006)*, Sep 2006.

**K. Clarno** and J. Gehin, “Physics Analysis of the LS-VHTR: Salt Coolant and Fuel Block Design,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR 2006)*, Sep 2006.

**K. Clarno**, V. de Almeida, E. D’Azevedo, C. de Oliveira, and S. Hamilton, “GNES-R: Global Nuclear Energy Simulator for Reactors, Task 1: High-Fidelity Neutron Transport,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR 2006)*, Sep 2006.

C. Forsberg and **K. Clarno** “The Advanced High-Temperature Reactor (AHTR): Flux Distribution and Dosimetry,” *Proceedings of the International Symposium on Reactor Dosimetry (ISRD-2005)*, May 2005.

D. Williams and **K. Clarno**, “Salt Selection for the LS-VHTR,” *Proceedings of the International Congress on Advances in Nuclear Power Plants (ICAPP 2006)*, Jun 2006.

**K. Clarno** and M. Adams, “Capturing the Effects of Unlike Neighbors in Single-Assembly Calculations,” *Proceedings of the Mathematics and Computations Division of the American Nuclear Society Topical Meeting (M&C-2003)*, Apr 2003.

**K. Clarno** and M. Adams, “Improved Boundary Conditions for Assembly-Level Transport Codes,” *Proceedings of Reactor Physics Division of the American Nuclear Society Topical Meeting (PHYSOR 2002)*, Sep 2002.

Conference Summaries

B. Rearden, **K. Clarno**, et al, “Criticality Safety Enhancements for SCALE-6.2 and Beyond,” *International Conference on Nuclear Criticality Safety (ICNC-2015)*, Charlotte, NC, Sep 2015.

**K. Clarno**, M. Berrill, S. Hamilton, R. Pawlowski, J. Turner, “Advanced Coupling Explorations for Parallel Coupled Neutronic and Thermal-Hydraulic Simulation,” *SIAM Conference on Parallel Processing*, Portland, OR, Feb 2014.

R. Pawlowski, et al, “Code Integration Strategies for Large-Scale Reactor Simulation,” *SIAM Conference on Parallel Processing*, Portland, OR, Feb 2014.

M. Piro, J. Banfield, **K. Clarno**, “Simulation of Thermochemistry and Isotopic Evolution of Irradiated Nuclear Fuel,” *Trans. Am. Nucl. Soc.*, Jun 2013.

B. Philip, **K. Clarno**, R. Sampath, M. Berrill, S. Allu, G. Dilts, and P. Barai, “The Advanced Multi-Physics (AMP) Package with an Application to Fuel Assemblies in Nuclear Reactors,” 2012 SIAM Annual Meeting, Minneapolis, MN, Jul 9–13, 2012.

J. Banfield, **K. Clarno**, S. Hamilton, G. I. Maldonado, B. Philip, and M. L. Baird, “Benchmarking of Software and Methods for Use in Transient Multidimensional Fuel Performance with Spatial Reactor Kinetics,” ICAPP ’12, Chicago, IL, Jun 24–28, 2012.

**K. Clarno**, S. Hamilton, B. Philip, R. Sampath, S. Allu, M. Berrill, P. Barai, and J. Banfield, “Integrated Radiation Transport and Thermo-Mechanics Simulation of a PWR Assembly,” *Trans. Am. Nucl. Soc*. **106**, 2012.

B. Philip, R. Sampath, S. Hamilton, M. Berrill, S. Allu, and **K. Clarno**, “Computational Approach to Nuclear Fuel Assembly Simulation,” *Trans. Am. Nucl. Soc*. **106**, 2012.

M. Piro, J. Banfield, S. Simunovic, T. Besmann, and **K. Clarno**, “Computational Thermodynamics in the Advanced Multi-Physics Code,” *Trans. Am. Nucl. Soc*. **106**, 1384–1386, 2012.

M. Piro, S. Simunovic, T. Besmann, and **K. Clarno**, “Coupling Thermodynamic Computations with Multi-Physics Nuclear Fuel Codes,” *Computer Coupling of Phase Diagrams and Thermochemistry* (CALPHAD), Berkeley, CA, Jun 3–8, 2012.

S. Hamilton, **K. Clarno**, B. Philip, R. Sampath, M. Berrill, S. Allu, M. Baird, and J. Banfield, “Coupled Radiation Transport and Thermomechanics Using the AMP and Denovo Codes,” *Twelfth Copper Mountain Conference on Iterative Methods*, Copper Mountain, CO, Mar 25–30, 2012.

B. Philip, **K. Clarno**, R. Sampath, M. Berrill, S. Allu, and G. Dilts, “The Advanced Multi-Physics (AMP Package),” *Twelfth Copper Mountain Conference on Iterative Methods*, Copper Mountain, CO, Mar 25–30, 2012.

B. Philip, **K. Clarno**, R. Sampath, M. Berrill, and S. Allu, “A Jacobian Free Newton Krylov Method with Multilevel Block Preconditioning for Multi-Domain Quasistatic Thermomechanics,” *Twelfth Copper Mountain Conference on Iterative Methods*, Copper Mountain, CO, Mar 25–30, 2012.

J. Banfield et al., “Quasi-Static Validation of the AMP Nuclear Fuel Performance Code,” *Trans. Am. Nucl. Soc.* **104**, Jun 2011.

P. Barai et al., “Strain-Based Continuum Damage Models for Nuclear Fuels,” *Trans. Am. Nucl. Soc*. **104**, Jun 2011.

S. Allu et al., “Initial Validation of the AMP Nuclear Fuel Performance Code,” *Trans. Am. Nucl. Soc*. **103**, Nov 2010.

G. Davidson et al., “Massively Parallel Solutions to the K-Eigenvalue Problem,” *Trans. Am. Nucl. Soc*. **103**, Nov 2010.

J. Galloway et al., “Generalized Isotopic Tracking Capabilities Within the 3-D BWR Nodal Simulator NESTLE,” *Trans. Am. Nucl. Soc*. **103**, Nov 2010.

G. Maldonado et al., “Integration of the NESTLE Core Simulator within SCALE,” *Trans. Am. Nucl. Soc*. **100**, Jun 2009.

Y. Wang et al., “Progress in the Integration of the 2D DG-FEM Sn Transport Solver Xuthus into SCALE,” *Trans. Am. Nucl. Soc*. **99**, Nov 2008.

T. Greifenkamp, **K. Clarno**, and J. C. Gehin, “Effect of Fuel Temperature Profile on Eigenvalue Calculations,” *Proceedings of the 2008 American Nuclear Society Student Conference*, Feb 2008.

**K. Clarno**, “Implementation of Generalized Coarse-Mesh Rebalance in NEWTRNX for Acceleration of Parallel Block Jacobi Transport,” *Trans. Am. Nucl. Soc.* **97**, Nov 2007.

S. R. Johnson and **K. Clarno**, “Implementation of Transport Synthetic Acceleration in NEWTRNX,” *Trans. Am. Nucl. Soc*. **97**, Nov 2007.

S. Hamilton, C. R. E. de Oliveira and **K. Clarno**, “Implementation of Time-Dependent Transport in NEWTRNX,” *Trans. Am. Nucl. Soc*. **97**, Nov 2007.

S. R. Johnson and **K. Clarno**, “Comparison of SCALE and MCNP Results for Computational Pebble Bed Benchmarks,” *Trans. Am. Nucl. Soc.* **96**, Jun 2007.

**K. Clarno**, C. W. Forsberg, and J. C. Gehin, “Physics Analysis of Coolant Voiding in the Advanced High Temperature Reactor,” *Trans. Am. Nucl. Soc*. **93**, Nov 2005.

**K. Clarno** et al, “Code-To-Code Benchmark of Coolant Void Reactivity (CVR) in the ACR-700 Reactor,” *Trans. Am. Nucl. Soc*. **93**, Nov 2005.

**K. Clarno** and M. L. Adams, “Recent Improvements in Boundary Conditions for Single-Assembly Calculations,” *Trans. Am. Nucl. Soc*. **89**, Nov 2003.

**K. Clarno** and Y.A. Hassan, “Development of a RELAP5-3D Three-dimensional Model of a VVER-1000 Nuclear Power Plant for Analysis of a Large-Break Loss-of-Coolant Accident,” *Trans. Am. Nucl. Soc*. **85**, Nov 2001.

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## Contact Information

**Email:**clarnokt@ornl.gov**Phone:**865.241.1894- orcid.org/0000-0002-5999-2978