A review of the meetings of the working group on the comparison of calculation models

Physical models used in various SFI analysis codes are reviewed and the results of the comparison of productions when the codes were applied to specific test cases are presented. Several representative codes are taken up for comparisons. The features that are compared and discussed in this review paper are; the fragmentation of molten fuel; heat transfer for Stage A (single phase coolant); heat transfer for Stage B (two phase coolant); hydrodynamics; and equation of the state of sodium. A brief description of the interaction conditions applied for the test cases is given followed by the results of comparisons. Instantaneous fuel fragmentation time of 10 ms. were assumed throughout the comparison calculations. The items being compared and discussed are the peak pressure and work done in Stage A, peak pressure in Stage B, time for expulsion of sodium from channel, and the work done in expelling sodium from channel. Results of comparisons of calculated values are presented in tables and figures. One of the main conclusions drawn from these comparisons is that if expulsion times are the main interest the various treatments adopted in different codes do not lead to very different predictions. (Aoki, K.)