The RAPID hybrid transport code, based on the fission matrix method, has been developed and previously proven successful on BEAVRS benchmark at hot-zero-power condition. In this work, it is extended to the BEAVRS model to include fuel and moderator temperature feedback. The bi-linear fission matrix interpolation technique was applied to several artificial fuel and moderator temperature distributions. For almost all cases, it provides an accurate calculation result with a keff difference smaller than 70 pcm and 2D pin-wise RMS error smaller than 1% compared to Serpent 2 Monte Carlo reference. In order to decrease the number of databases needed, a plane interpolation routine is developed, which de-couples the fuel and moderator temperature. The RAPID calculation with the plane interpolation reports a similar accuracy to that with the bi-linear interpolation. The bi-linear interpolation required 24 database points from Monte Carlo calculations, while the plane interpolation only needed 10. The plane interpolation allows RAPID to prepare fewer databases while preserving a high accuracy.
All Science Journal Classification (ASJC) codes
- Nuclear Energy and Engineering