The simulation of start-up of natural circulation boiler based on the Astrom-Bell model

This paper presents a numerical investigation on the dynamic analysis of steam and water system of the natural circulation boiler SHL35.2.5/AI with the software MATLAB/SIMULINK. Based on the four-order Astrom-Bell model, a model applicable the specific boiler was established, casting light on the changes in parameters of designed, cold start and varying load condition. And a curve of cold start is obtained, which can be taken as reference for practical operation. In addition, in the condition of varying load, our model captured the phenomenon of false water level, and according analysis is made. Our study introduces a feasible method of simulation on the dynamic analysis of steam and water system on other boilers as well.