Ryan Stewart

I am a first year PhD student at Oregon State University working under Dr. Todd Palmer. I obtained my masters degree from Idaho State University (ISU) while working under Dr. Chad Pope.

My masters work focused on helping create a benchmark model for the Experimental Breeder Reactor II (EBR-II) for the International Reactor Physics Experiment Evaluation Project (IRPhEP). The IRPhEP handbook is utilized by the reactor physics community as a tool to aid in the validation of calculational techniques and data. The focus of my work was to determine the viability of homogenization to specific areas of the core in the hopes of reducing the size of the input file, and the time required to run a simulation. To ensure the process produced accurate results, a sensitivity analysis was performed on a driver assembly for both a heterogeneous and homogeneous model. A full copy can be found here.

For the summer of 2017, I worked in conjunction with Idaho National Lab (INL) and ISU on developing and implementing Functional Expansion Tallies (FETs) in the neutronics code Shift for the Exascale Computing Project. The FETs are meant to create a seamless transition for data from neutronics to computational fluid dynamics codes to allow for fully coupled reactor physics problems to be solved. A short paper on the work can be found here.

Currently, I am working with Dr. Palmer to procure funding for additional fast reactor research with the proposed Versatile Fast Neutron Source at INL.

I can be reached via email at stewryan@oregonstate.edu.

Research Interests

  1. Fast Reactor Core Analysis
  2. Reactor Physics
  3. Reactor Benchmarking


  1. R. Stewart, C. Pope and E. Ryan, “Fast spectrum reactor fuel assembly sensitivity analysis”, Annals of Nuclear Energy, vol. 110, pp. 1091-1097, 2017.

Other Interests

I love visiting national parks/monuments (I have already visit over 10) and hiking just about anywhere. Along with that, I enjoy backpacking and spending my weekends in the woods whenever possible. I love playing just about all types of board games, from simple card games to multi-hour/day board games. I also enjoy cooking, foraging, canning, and exploring new places.