Nuclear Reactor Thermal Analysis
Thermal hydraulics analysis of supercritical water reactor core design
Jianguo Zhong, Michael Podowski
Abstract: This paper started with a literature survey of development the supercritical flow reactor core design, various coolant flow path designs were discussed: conventional one-pass flow arrangement, two-pass and the three-pass coolant flow geometry. A simple 1-D model was developed for the one-pass and two-pass flow design to find the maximum flow bulk temperature and case temperature in the fuel assembly. In the implementation of the model, an accurate prediction of heat transfer coefficient was vital, which was also much complicated for the supercritical flow since the flow property changed substantially at the pseudo-critical region. Study showed that classical Dittus-Bolter correlation disagreed with the experimental results significantly. The in-house CFD code, NPHASE-CMFD, was implemented on 1-D supercritical water reactor to simulate the bulk flow and case temperature distribution in the supercritical water reactor, which provided useful guidance of supercritical water reactor design from engineering purpose. 1. Introduction
In the development of next generation nuclear power plant, higher efficiency and more compact size of reactor core is important. Among the six next generation nuclear power plant, supercritical water-cooled reactor (SCWR) are promising because of their high thermal efficiency (i.e., about 45% vs. about 33% efficiency for current Light Water Reactors, LWRs [1]) and considerable plant component simplification with the direct cycle. In the SCWR, since the coolant in the core is operated above the critical pressure, no phase change process exists in the core in the heat transfer process, eliminating the boiling related issues such as critical heat flux and local dry out problem. Also, in the SCWR, there is no need for recirculation and jet pumps, a pressurizer, steam generators, and dryers. Lots of SCWR reactor core design
Jianguo Zhong, Michael Podowski
Abstract: This paper started with a literature survey of development the supercritical flow reactor core design, various coolant flow path designs were discussed: conventional one-pass flow arrangement, two-pass and the three-pass coolant flow geometry. A simple 1-D model was developed for the one-pass and two-pass flow design to find the maximum flow bulk temperature and case temperature in the fuel assembly. In the implementation of the model, an accurate prediction of heat transfer coefficient was vital, which was also much complicated for the supercritical flow since the flow property changed substantially at the pseudo-critical region. Study showed that classical Dittus-Bolter correlation disagreed with the experimental results significantly. The in-house CFD code, NPHASE-CMFD, was implemented on 1-D supercritical water reactor to simulate the bulk flow and case temperature distribution in the supercritical water reactor, which provided useful guidance of supercritical water reactor design from engineering purpose. 1. Introduction
In the development of next generation nuclear power plant, higher efficiency and more compact size of reactor core is important. Among the six next generation nuclear power plant, supercritical water-cooled reactor (SCWR) are promising because of their high thermal efficiency (i.e., about 45% vs. about 33% efficiency for current Light Water Reactors, LWRs [1]) and considerable plant component simplification with the direct cycle. In the SCWR, since the coolant in the core is operated above the critical pressure, no phase change process exists in the core in the heat transfer process, eliminating the boiling related issues such as critical heat flux and local dry out problem. Also, in the SCWR, there is no need for recirculation and jet pumps, a pressurizer, steam generators, and dryers. Lots of SCWR reactor core design