Numerical Advisory Solutions
Nuclear Fuel Analysis

Nuclear Fuel Analysis

NAS personnel have extensive experience in the development and application of analytical methods in support of safety analyses and fuel loads. Our technical staff has experience in development of computer codes and analytical models for nuclear reactor cores. NAS has developed reactor kinetics methods and models for coupled thermal hydraulic and neutronics analysis. These applications have involved simple point kinetics approaches, one-dimensional kinetics and advanced three-dimensional kinetics components.
Core Physics Analysis and Review
NAS personnel have developed nuclear data generation models and interface codes to manipulate the large and complex data sets that are required to support the multi-dimensional kinetics models. We have applied these models to international reactor transient benchmark projects involving the complex interaction between the reactor core and the nuclear reactor system. These models have also been used by other groups in the nuclear industry to support such projects as the behavior of nuclear fuel assemblies under extreme transient conditions.
Nuclear Fuels and Analysis
NAS personnel have performed reload analyses for many of the existing BWRs and PWRs, as well as independent detailed technical reviews of fuel vendor thermal hydraulic and neutronic analyses. NAS has the reload analysis experience to support owner's reviews fuel vendor reload analysis and core design optimization for utilities. We have staff that were previously qualified with fuel vendor methods and therefore can prepare or review work for fuel vendors to support schedule constraints. NAS also has extensive analytical methodology development experience, including Regulatory Guide 1.203 (Transient and Accident Analysis Methods) implementation and defense to the regulator.
Reload and Core Design
NAS personnel have participated in numerous BWR and PWR reload review teams and core design teams. From the verification of vendor inputs to the completion of complete core designs, NAS personnel have been involved with all phases of a reload. NAS personnel have used vendor reload/core design software and are proficient with the Studsvik code system, including CASMO/SIMULATE.
Fuel Reliability
NAS personnel have supported the development of the EPRI BWR crud deposition models and a risk assessment tool, CORAL, to predict tenacious crud deposition and assess the risk for crud-induced fuel cladding corrosion issues. NAS has also supported the development and application of the EPRI Boron-induced Offset Anomaly (BOA) risk assessment tool to evaluate corrosion, physical chemistry, and thermal-hydraulic effects for the prediction of corrosion product release. NAS currently maintains CORAL and BOA for EPRI in choosing replacement cabling, conduits, and the conduit routing.
Spent Fuel Management
NAS personnel have supported detailed analyses of spent fuel pools (SFP), independent spent fuel storage installation facilities (ISFSF), spent fuel shipping and storage casks and operating procedures associated with loading and unloading casks and shipping fuel. Additional details can be found on our Waste Management page.