O’Donnell Consulting Engineers, Inc. has specialized expertise in nuclear component design, analyses, review, and verification. We offer a combination of analytical, design, testing and technical problem solving skills to meet the needs of nuclear power industry clients. We utilize linear and non-linear finite element analyses to simulate complex thermal transients and structural responses of various components for nuclear power plants.
Our senior engineers have expertise in design, materials, thermal analysis, fatigue, vibration /seismic analyses, and fracture mechanics in extending the life of critical components. Dr. William J. O’Donnell, President, co-invented the Mechanical Stress Improvement Process used to relieve stresses in welded joints subjected to stress corrosion cracking. The process has been applied in many nuclear power plants throughout the world.
Our engineers have also contributed to the development of analysis methods for fatigue, fracture, limit analysis, plasticity, creep ratcheting, dynamic loads and elevated temperature design – successfully serving clients (major nuclear utilities and U.S. Nuclear Steam Supply System manufacturers) from England, Japan, Germany, France, and Spain as well as across the United States. A few of the components we have worked on include:
- Structural Design and Analysis
Three dimensional finite element analysis was used to design numerous Class 1 nuclear components. Stress indices were developed for pressure and external loadings on piping components in simplified design procedures.
- Tube-and-Tubesheet Analysis
General methods for calculating stresses and strains due to mechanical and thermal-induced loads were developed for tubesheets. Extensive development work has been completed on tube-to-tubesheet joints. Inelastic analyses were used to quantify the hydraulic pressures needed for the expanded tubes, and the pressure needed in the neighboring tubes to protect the ligaments.
- Design Criteria
The U.S. Nuclear Regulatory Commission (NRC) and Westinghouse jointly chose O'Donnell Consulting to develop design criteria and methods for the acceptance of flaws using fracture analysis of perforated tubesheets in steam generators to satisfy NRC requirements. The solution applied finite element methods to determine nominal stresses in the tubesheet subjected to thermal and mechanical loads. Failure modes for leaks and criteria for failure were investigated.