Dynamic simulation of a natural circulation drum boiler considering stress in the drum wall

摘要

A mathematical model is developed to simulate the behavior of a natural circulation drum boiler. The present study investigates not only the fluid dynamics of the boiler and the heat conduction process in the drum shell but also the generated effective stresses in the drum metal wall. The model is established based on physical laws. The results obtained by the simulation could address the understanding of interactions of state variables inside out. The performance parameters can n be estimated at any operating conditions, which include the drum pressure, the volume of entire water, the steam quality at the riser top, the liquid level in the drum, and the distribution of temperature and stress in the drum shell. This study demonstrates that the model can describe the complex behavior of the natural circulation drum boiler with the given operating scenarios before actual plant implementation. The simulation result has been validated with the start-up data from a 2MWe circulating fluidized bed power plant.