Recent Developments of the SPACE Code

The SPACE (the Safety and Performance Analysis Code for Nuclear Power Plants) code adopts advanced physical modeling of two-phase flows, mainly two phase three-field models which comprise gas, continuous liquid, and droplet fields. But it has been modified to be able to handle the classical two-phase two-field model by user's selection. It has the capability to simulate 3D effects by the use of structured and/or non-structured meshes. The SPACE code has been developed and validated successfully. We submitted the topical reports to regulatory body for review in 2013. Since then, SPACE code developers and the reviewers are exchanging the questions and answers concerning to the topical reports. In this paper, recent advances in the SPACE code will be briefly presented. First, the model improvements for multi-dimensional applications are introduced with a few validation results. Second, optional two-phase two fluid model development activities are described. The comparison of calculation results with two-phase three fluid model case is also presented. Third, nonphysical phasic velocities for a dispersed field were corrected by improving pressure drop by wall drag and from loss. Fourth, an improved CHF model for pool boiling condition based on instability theory is also introduced. SPACE code has been developed to be used for a safety analysis of PWR design