Computational model for prediction of water level inside Vertical U-tube Steam Generators (UTSGs) of typical PWR

Abstract

Maintaining water level inside steam generators in a typical Pressurized Water Reactor (PWR) particularly during low power has always been a significant challenge in the operation of Nuclear Power Plants (NPPs). Variation in power leads to fluctuations in the water level and stabilizing the water level in the steam generator prevent damage to turbines, core and tripping of reactors. This research presents a computational model for predicting water levels in U-tube vertical steam generators (UTSGs) of PWRs during transients. The model's level predictive capability was validated through cross-calculations with actual data of $998M{W}_{\text{th}}/340M{W}_e$ Nuclear Power Plant (NPP). The methodology involves developing computational frameworks from the Irving model and collecting extensive data from existing PWR systems of $998M{W}_{\text{th}}/340M{W}_e$ NPPs to assess model accuracy. The results demonstrated that the predictive control method effectively maintained optimal water levels within the steam generators, minimizing discrepancies between predicted and actual values. The ramp response consistently provided smoother and more accurate predictions that closely matched the behavior of the actual system. The cross calculations with actual data further substantiate the model's effectiveness, demonstrating its potential as a reliable tool for real time monitoring and control in steam generators. These findings contribute to the improvement of safety and efficiency in nuclear power plant operations.