Analysis of the Hydraulic Resistance of a Water Wall Based on a Distributed Parameter Model in a Supercritical Once Through Boiler

Abstract

Accurate prediction of the hydraulic resistance is helpful for the safe operation of a water wall in a supercritical boiler. In this paper, the density distribution for the resistance calculation of a water wall at the supercritical pressure is numerically analyzed, and a distributed parameter model of the hydraulic resistance is developed in a downfired 600 MWe supercritical boiler using a threedimensional temperature distribution. The results show that the difference in the density along the radial direction is small and that the hydraulic resistance of the water wall tubes at the supercritical pressure is affected by the critical phenomenon of the working fluid and the allocation of heat flux of the boiler. The simulation cases and in situ operation data demonstrate the model. The model provides a new analysis method for the hydraulic resistance characteristics of a water wall in this thermodynamic system, and the derived model builds a foundation for developing flow monitoring and a thermalhydraulic design.