Program
Nuclear Engineering
College
Engineering
Student Level
Doctoral
Location
PAÍS Building
Start Date
10-11-2022 11:00 AM
End Date
10-11-2022 1:00 PM
Abstract
Fluoride Salt Cooled High-Temperature Reactors (FHRs) use particle fuel, graphite moderator, and molten fluoride salt coolant for power generation and process heat applications. The main loop of the FHR is a closed loop, operating at slightly above atmospheric pressure, with fluoride salt temperatures exceeding 600 °C. Reliable high-temperature molten salt pumps are critical to the successful deployment of FHRs. To stabilize the rotating shaft and reduce the associated coefficient of friction, molten salt pumps require well-designed bearings. Therefore, it is necessary to study the detailed hydrodynamic performance of bearings under high-temperature molten salt conditions. In the current study, a computational fluid dynamics (CFD) software package, STAR-CCM+, was used to predict the performance of fluoride salt-lubricated bearings. To validate the numerical model, the numerical model was validated and validated based on analytical solutions derived from the Reynolds equation and experimental data published in the literature, respectively. Good agreement was observed between the simulated results and the analytical solution and experimental data, with a maximum relative difference of less than 5%. A validated numerical model was then used to predict the pressure distribution, applied static load, and power loss for high-temperature fluoride-salt lubricated bearings with various Sommerfeld numbers. In addition, parametric analysis was performed to investigate the effect of the bearing's axial and helical grooves on the applied static loads and power losses. It was found that under the same fluoride salt lubrication conditions, bearings with helical grooves produced minimal power losses and applied static loads compared to bearings without grooves and with axial grooves. Advanced Thermal-Hydraulics Laboratory (ATHL) has a fluoride-salt-lubricated bearing test facility that is used for investigating the static and dynamic performance of bearings. The facility will offer unique features to test different bearings at speeds as high as 3600 RPM and specific loads facility design will with advanced modern instrumentation and dynamic testing capability. Our design consists of a bearing tester, a drive motor, a molten salt reservoir tank, a loading system, thermal insulation, and instrumentation. The scalability evaluation of fluoride salt pumps provides guidelines and insights for large-scale pump designs that are useful for FHR developers.
Molten Salt Pump Bearing Design and Test
PAÍS Building
Fluoride Salt Cooled High-Temperature Reactors (FHRs) use particle fuel, graphite moderator, and molten fluoride salt coolant for power generation and process heat applications. The main loop of the FHR is a closed loop, operating at slightly above atmospheric pressure, with fluoride salt temperatures exceeding 600 °C. Reliable high-temperature molten salt pumps are critical to the successful deployment of FHRs. To stabilize the rotating shaft and reduce the associated coefficient of friction, molten salt pumps require well-designed bearings. Therefore, it is necessary to study the detailed hydrodynamic performance of bearings under high-temperature molten salt conditions. In the current study, a computational fluid dynamics (CFD) software package, STAR-CCM+, was used to predict the performance of fluoride salt-lubricated bearings. To validate the numerical model, the numerical model was validated and validated based on analytical solutions derived from the Reynolds equation and experimental data published in the literature, respectively. Good agreement was observed between the simulated results and the analytical solution and experimental data, with a maximum relative difference of less than 5%. A validated numerical model was then used to predict the pressure distribution, applied static load, and power loss for high-temperature fluoride-salt lubricated bearings with various Sommerfeld numbers. In addition, parametric analysis was performed to investigate the effect of the bearing's axial and helical grooves on the applied static loads and power losses. It was found that under the same fluoride salt lubrication conditions, bearings with helical grooves produced minimal power losses and applied static loads compared to bearings without grooves and with axial grooves. Advanced Thermal-Hydraulics Laboratory (ATHL) has a fluoride-salt-lubricated bearing test facility that is used for investigating the static and dynamic performance of bearings. The facility will offer unique features to test different bearings at speeds as high as 3600 RPM and specific loads facility design will with advanced modern instrumentation and dynamic testing capability. Our design consists of a bearing tester, a drive motor, a molten salt reservoir tank, a loading system, thermal insulation, and instrumentation. The scalability evaluation of fluoride salt pumps provides guidelines and insights for large-scale pump designs that are useful for FHR developers.
