Thermal-hydraulics in intermediate plena of pool-type LMFBR, 3

A visualization experiment in a water-filled model plenum with a sloping cold floor, adiabatic short sidewall, heated long sidewall and either heated or adiabatic roof to investigate flow pattern of the intermediate plena at pool type LMFBR has carried out, and a finite element analysis of laminar natural convection in the model trapezoidal plenum are conducted. The results of the experiments and analysis are summarized as follows. (1) The velocity near the horizontal roof decreased with incleasing non-dimensional number S(Grsup(*).Pr2)sup(1/5) obtained by thermal stratification parameter, it approached zero above S(Grsup(*) Pr2)sup(1/5) of 20. (2) Flow pattern in the model plenum by natural convection are divided roughly into upper rectangular region and lower triangular region. (3) Approximately qualitative agreement between the results of the analysis by FEAT code and experimental results was obtained, and this code was proved applicability. (author)