ICONE23-1375 Pressure-Drop Analysis of a Re-Entrant Fuel Channel In a Pressure-Channel Supercritical Water-Cooled Reactor

Abstract

Modern Generation-III Nuclear Power Plants (NPPs) equipped with water-cooled reactors have gross thermal efficiencies of approximately 30-36%, which are significantly less than those of advanced fossil-fuel and natural-gas thermal power plants (55-62%). Therefore, global effort to progress Generation-IV reactor concepts and NPPs are required to meet the demand for clean, non-fossil-based electrical production. The main objective of this paper is to determine a pressure drop across a fuel channel of a SuperCritical Water-cooled Reactor (SCWR). A generic 1200-MWel SCWR has inlet and outlet temperatures of 350°C and 650°C, respectively, and an inlet pressure of 25 MPa. With such high operating temperatures and pressures, an SCWR NPP can achieve gross thermal efficiencies of approximately 45 - 48%, which is a substantial improvement over the currently operating Generation-III NPPs. For this purpose, a Re-Entrant-Channel design and its associated 78-element fuel bundle are selected as a basis for this analysis. An investigation of a pressure drop resulting from friction, gravity, acceleration and local losses at supercritical conditions has been performed on a basis of one-dimensional steady-state analysis. With this objective, a thermal-hydraulic code has been created with MATLAB, which calculates the pressure drop across a 5-m heated length of a vertical fuel channel. The total pressure drop across the channel was estimated to be about 60 kPa.