Fuel Rod Expertise for the Nuclear Power Industry
KW Consulting provides quality services in the following areas:
- PWR fuel rod design analysis assistance and review
- PWR fuel rod design analysis training
- Fuel rod performance model development and licensing
- Plant licensing review and update
- Independent review of fuel reliability issues
PWR fuel rod design analysis assistance and review
As a result of the new level of competition associated with impending deregulation of the utility industry, fuel vendors are continuously developing new fuel rod designs which are capable of operation at the more limiting conditions required to improve fuel cycle economics and reduce overall costs. Many of these designs are based on cutting edge technology. Independent review and analysis of these designs by the utility operators of the nuclear plants is necessary to facilitate their understanding of the design and its limitations and to assess the value and associated risk of the proposed design change for their operating conditions. KW Consulting provides the background and expertise necessary for assessment of these design changes, either by doing a complete review for their clients or by assisting the client's in-house staff.
In the areas of fuel rod design and fuel performance evaluations, KW Consulting will use the FRAPCON-3 steady state fuel performance code to perform quantitative assessments of key fuel rod performance parameters, if required. The FRAPCON code was developed under NRC sponsorship to be used as an audit tool in evaluating vendor fuel rod designs and fuel rod performance models. The code calculates the fuel rod behavior as a function of time for all significant fuel rod parameters, including fuel and cladding temperatures, cladding strain, cladding corrosion and hydriding, cladding axial growth, fuel swelling and densification, fission gas release, and rod internal pressure.
The recent update of the FRAPCON-2 code to FRAPCON-3, performed by Pacific Northwest National Laboratory (PNNL), accounts for high burnup effects and extends the applicability of the code to fuel burnup levels up to 65 GWD/MTU. Material property and performance models which have been updated include fission gas release, fuel thermal conductivity, fuel swelling, contact gap conductance, cladding corrosion and hydriding, cladding mechanical properties and cladding axial growth. Each updated material property and performance model was calibrated to well characterized high burnup performance. FRAPCON-3 development was completed in 1997 and the code was made available to the nuclear power industry in early 1998 as a state-of-the-art fuel performance tool. KW Consulting has access to the FRAPCON-3 source code so that, if required, code modifications may be made to model vendor-specific advanced fuel design features.
PWR fuel rod design analysis training
Current licensing requirements demand that operating personnel in today's nuclear plants have a broad understanding of all aspects of the fuel performance and design. KW Consulting can meet this need by providing high quality training in fuel rod design and performance to utility personnel.
Dr. Weiner of KW Consulting has substantial experience in the development and presentation of fuel rod design training seminars. He was responsible for the development of fuel rod design training sessions for several years while working for the Westinghouse Commercial Nuclear Fuel Division and has presented detailed training sessions in the United States, Asia and Europe.
Fuel rod performance model development and licensing
The behavior of a fuel rod during reactor operation is complex and is typically evaluated using sophisticated computer code with embedded multi-variable equations which define the expected operation of the fuel as a function of key operating and material characteristics. There equations are derived based on experimental data coupled with an understanding of the basic phenomenological behavior. Once these models are developed, it is often necessary to obtain NRC or other regulatory agency approval in order to use these tools in design applications.
KW Consulting can provide the expertise necessary to derive these computer models based on the more than 40 years combined experience in development, licensing and maintenance of these types of programs for one of the largest pressurized water reactor (PWR) vendors in the world. Customers who can benefit from this service include PWR fuel vendors who develop performance models for use in evaluation and design of their own fuel and nuclear utilities who desire to have independent design tools capable of analysis of their own fuel rod performance.
Plant licensing review and update
Nuclear utilities are required to maintain an up to date version of the plant design and safety analyses bases. Utilities who are on the NRC watch list may be required by NRC to perform detailed review and confirmation of the specific analyses performed for their plant to support plant startup after shutdown. The review and update of these documents must be done by knowledgeable personnel who are capable of understanding and critiquing the details of the existing analyses. KW Consulting can provide the review and updating resources needed by utilities to obtain quality documentation of their design and safety analyses bases.
Independent review of fuel reliability issues
While nuclear power plants are designed to prevent the failure of the fuel rod cladding, thus preventing release of radioactive isotopes to the reactor primary coolant system, it is impossible to prevent a small number of fuel rod failures. These failures are considered to be a potential safety concern by nuclear regulatory authorities, and it is a high priority for utilities which experience fuel defects to perform detailed assessments of the failure cause to establish the risk of additional fuel rod failures. KW Consulting can provide independent review services for evaluation of fuel defects and assist the customer in performing risk assessments for future operation, facilitating a more rapid restart of the plant.
