Dr. Clarno is a tenured Associate Professor in the Nuclear and Radiation Engineering program at the University of Texas at Austin with a research focus on computational nuclear energy, including algorithm development for radiation transport and reactor multiphysics. Dr. Clarno worked 15 years at Oak Ridge National Laboratory (ORNL), and was also assistant professor at the University of Tennessee-Knoxville as joint faculty member in nuclear engineering. He has led national, multi-institutional high-performance computing (HPC) research programs, including the Consortium for Advanced Simulation of Light Water Reactors (CASL) as Interim Director; the CASL Physics Integration (PHI) Focus Area; modernization of the SCALE nuclear analysis software; development of the Advanced Multi-Physics (AMP) fuel performance code; and a portfolio of ORNL laboratory-directed strategic research projects. As a technical contributor at ORNL, Dr. Clarno has developed high-performance computing software, researched new algorithms for SCALE, and performed analyses of nuclear reactors for a diverse set of US Nuclear Regulatory Commission (NRC) and DOE projects. 

Dr. Clarno’s primary research areas include:

• Multiphysics coupling methods for advanced simulation of nuclear reactors to integrate analyses and improve accuracy;
• Multiscale neutronics, fuel performance, and thermal-hydraulics to enable high resolution analyses in coupled physics applications;
• Design, optimization, and analysis of advanced commercial and test reactor concepts;
• Integration of software to optimize advanced manufacturing of nuclear technologies; and
• Propagation of uncertainties through multiphysics applications to optimize experiments.

Selected Publications

“Capturing the Effects of Unlike Neighbors in Single-Assembly Calculations,” Nuclear Science and Engineering, 149(2), 182–196, DOI: 10.13182/NSE04-31, (2005).

“Assessment of Candidate Molten Salt Coolants for the Advanced High Temperature Reactor (AHTR),” ORNL/TM-2006/12, DOI: 10.2172/885975, (2006).

“Denovo–A New Three-Dimensional Parallel Discrete Ordinates Code in SCALE,” Nuclear Technology, 171(2), 171–200, DOI: 10.13182/NT171-171, (2010).

“Coupled thermochemical, isotopic evolution and heat transfer simulations in highly irradiated UO₂ nuclear fuel,” Journal of Nuclear Materials 441, 240–251, DOI: 10.1016/j.jnucmat.2013.05.060, (2013).

“A Parallel Multi-Domain Solution Methodology Applied to Nonlinear Thermal Transport Problems in Nuclear Fuel Pins,” Journal of Computational Physics, 286, 143–171, DOI: 10.1016/j.jcp.2015.01.029, (2015).

“The Virtual Environment for Reactor Applications (VERA): Design and architecture,” Journal of Computational Physics, 326, 544–568, DOI: 10.1016/j.jcp.2016.09.003, (2016).

Recent Publications

Salko, W. Pointer, M. Delchini, W. Gurecky, K. Clarno, et al., “Implementation of a Spacer Grid Rod Thermal Hydraulic Reconstruction (ROTHCON) Capability into the Thermal Hydraulic Subchannel Code CTF,” Nuclear Technology, DOI: 10.1080/00295450.2019.1585734, (2019).

Toptan, R. Salko, M. Avramova, K. Clarno, D. Kropaczek, “A new fuel performance modeling framework, CTFFuel, with a case study on the fuel thermal conductivity degradation,” Nuclear Engineering and Design, 341, 248-258, DOI: 10.1016/j.nucengdes.2018.11.010, )2019).

Kim, M. Williams, D. Wiarda, K. Clarno, “Development of the Multigroup Cross Section Library for the CASL Neutronics Simulator MPACT: Method and Procedure,” Annals of Nuclear Energy,133, 46-58, DOI: 10.1016/j.anucene.2019.05.010, (2019).

Capps, S. Stimpson, K. Clarno, B. Wirth, J. Rashid, “Assessment of the analysis capability for core-wide PWR pellet-clad interaction screening of Watts Bar Unit 1,” Nuclear Engineering and Design, 333, 131–144, (2018).