Modeling and simulation of an integrated regenerative transcritical cycle with a small modular reactor

Abstract

In recent years, small modular reactors (SMR) have gained substantial development advancement and world-wide acceptance. While various advanced power cycles (e.g. supercritical CO2 Brayton cycle) have been proposed for Gen IV reactors, the steam cycle remains the only cycle for light water reactors. In this work, a unique regenerative transcritical power cycle using small molecule organic fluids (methanol and ethanol) was modeled with the reactor coolant loop of a small modular light-water reactor. In addition to modeling the thermodynamic cycle and associated transport processes for prominent components, the solution algorithms of the combined cycle model using MATLAB/REFPROP are illustrated in this article. The simulation results show that, by leveraging the superior thermophysical properties around the critical points of the working fluids, the transcritical methanol/ethanol cycles have shown similar performance as the steam cycle in terms of thermal efficiency and power output. With further system optimization, the regenerative transcritical cycle is expected to offer increased power output from the small modular light-water reactor as an alternative energy conversion system.