Simulation research on corrosion and thinning characteristics of water wall tubes based on electric field array

Abstract

During service, the water wall tube will inevitably corrode due to various corrosive gases such as SO2, HCl, H2S, etc. To prevent the occurrence of tube burst accidents caused by thinning and income-pressure resistance of the water wall tube, it is necessary to monitor the wall thickness of the water wall tube row in real-time. This paper proposes an array-based method for monitoring the thickness of the water wall tube row, and the different corrosion characteristics models of the water wall tube row are established by using the finite element analysis software Maxwell. Based on the model, the influence of tube wall thickness and material on measurement accuracy is analyzed by current density distribution and electric field intensity. The error of calculation formula is analyzed by simulating different corrosion conditions of tube wall thinning. The calculation formula of the wall thickness after the corrosion of the water wall tube row and the correction formula of the wall thickness of a single water wall tube with the correction coefficient α of 3 are determined. And put forward to define the ”generalized average thickness” of the water wall corrosion of multiple tubes, and determine the correct formula for calculating the thickness of the water wall tube row with a correction coefficient β of 0.85 to 0.95.