Nuclear Systems Analysis
Analysis for Commercial and Military Nuclear Systems
ES3 has a nuclear systems group that provides research, development, and analysis for commercial nuclear power systems for energy production as well as nuclear weapon effects analysis for DOD weapons systems and components.
ES3 provides criticality, burnup, and nuclear fuel material performance research for commercial power applications. ES3 provides simulation services through radiation transport and nuclear hardness and survivability analysis with a specialized software suite called PENTRAN.
PENTRAN Simulation Suite is sold as a software product or can be employed by ES3 professionals to provide radiation transport calculations.
We preserve the computational integrity of mission-critical systems by modernizing legacy trusted Fortran (including FORTRAN II, IV, 66, 77, modern Fortran) and other codes ensuring full traceability and reproducibility against historical benchmarks, then extend these trusted solutions to address larger-scale or higher-fidelity problems with confidence.
Nuclear Hardness and Survivabillity
ES3 supports government agencies, defense contractors, aerospace organizations, and critical infrastructure operators with comprehensive nuclear effects and survivability assessments. Our multidisciplinary approach combines physics-based modeling, engineering analysis, and system-level evaluation to identify vulnerabilities and improve resilience. Our nuclear hardness and survivability services include:
- Nuclear weapon effects characterization
- System survivability analysis
- Radiation effects analysis
- EMP and electromagnetic effects analysis
- Nuclear environments analysis,
- Nuclear hardness assurance support
Monte Carlo Photon Transport Simulation
Commercial Power Applications
ES3 supports commercial nuclear power, advanced reactor development, fuel cycle technologies, defense applications, research institutions, and regulatory programs with high-fidelity computational analysis and custom nuclear data solutions. Our team includes licensed Professional Engineers (PE) with over 25 year of experience providing the following services:
- Radiation Transport Analysis using MCNP and/or PENTRAN
- Reactor shielding design and optimization
- Nuclear fuel criticality safety analysis
- Fuel burnup and fuel cycle analysis
- Materials modeling for fuel composition and irradiation effects
- Generation of a customized nuclear cross section library
PENTRAN Software
ES3 is an exclusive dealer of the PENTRAN simulation suite, supporting tools, cross section generation, and consulting for nuclear applications. PENTRAN is a Parallel 3-D hybrid Sn (Discrete Ordinates) – CRT (Characteristic Ray Trace) deterministic radiation transport code, with tools for CADIS adjoint support for Monte Carlo variance reduction (including MCNP®). PENTRAN provides users with a 3-D mesh generation capability to build 3-D Sn geometries to set up, run, and visualize PENTRAN 3-D Cartesian block adaptive mesh solutions with material mass/volume balance capabilities with any standard multigroup cross sections.
The PENTRAN suite runs best on a Linux operating system but can also be used on Windows 10 or 11 laptop running WSL/Ubuntu Linux with at least 12 Gb of RAM and 4 virtual CPUs.
Note: PENTRAN access falls under ECCN 0D999(b) (US Dept of Commerce, 21 Mar 2011), and is generally accessible for US persons and people from most countries (excluded: Cuba; Iraq; Iran; North Korea; Sudan; Syria).
Legacy Code Modernization
ES3 preserves the computational integrity of mission-critical systems by modernizing legacy trusted Fortran (including FORTRAN II, IV, 66, 77, modern Fortran) and other codes ensuring full traceability and reproducibility against historical benchmarks, then extend these trusted solutions to address larger-scale or higher-fidelity problems with confidence. Our nuclear engineers have combined 30+ years of experience modernizing legacy FORTRAN codes into modern FORTRAN, MATLAB, and/or Python to bring the codes up to date while preserving the computational efficiency that FORTRAN has always provided.