New inverted hydride fuel design concept for pressure tube type super critical water reactors

In this study, an innovative core design having inverted configuration has been pro- posed for pressure tube type supercritical water reactors. In this design the relative po- sitions of fuel and coolant have been inverted and U-Th-Zr-hydride fuel has been used. A coupled neutronics and thermal hydraulics analysis was done for the proposed In- verted Pressure Tube Type (IPTT) SCWR. The neutronics analysis was carried out by using a 3D fine mesh diffusion theory code and thermal hydraulics calculations were done by using single channel model. These two codes were coupled with each other by a link code. The average outlet temperature for the proposed IPTT-SCWR was found to be 625°C with maximum clad surface temperature (MCST) under the design limits i.e. below 850°C. Moreover a core loading pattern has also been proposed to achieve uni- form radial power distribution and lower cladding surface temperature.