System Code Analysis of ATLAS Facility Including Heat Loss Evaluation

Abstract

There have been many efforts to improve the
prediction capability of the system codes such as
RELAP5, MARS-KS, and SPACE using ATLAS
experimental data. However, since the heat loss of the
ATLAS has not been reflected correctly in the code
input model, there have been differences between the
experimental data and the code prediction results. This
difference can induce a distortion in maximum cladding
temperature, natural circulation flow rate in primary
system, cooling and de-pressurizing rate of the system.
To improve the prediction capability of the system
code input model for the ATLAS, this study performed
followings: 1) evaluation of the ATLAS heat loss using
the experimental data, 2) modeling/application of the
local heat loss quantification to the ATLAS input model,
3) transient simulation with heat loss, and 4) comparison
with the experimental data.