Numerical Simulation And Optimize Research Of Combustion System Of Circulating Fluidized Bed Boiler

Due to its unique advantages such as low pollution emissions and high combustion efficiency,circulating fluidized bed boilers have received the significant attention.At present,the power generation technology is mainly based on coal combustion,and circulating fluidized bed,as a new clean coal combustion technology,has been well developed in recent years.Before the design of large-scale circulating fluidized bed boilers,it is necessary to grasp the distribution of flow and temperature in the furnace clearly.However,the data obtained by the traditional measuring method has great limitations,and this has hindered the study of large-scale circulating fluidized bed boilers.With the advancement of computer technology and the perfection of combustion theory,numerical simulation has become another important method for the analysis of combustion process in the furnace.This paper takes the Dongguo DG470/9.71-1 circulating fluidized bed boiler as the research object,and the modeling of the model and the numerical simulation experiment of combustion are carried out.According to the experimental results,the rationality of the constructed model was analyzed and optimization research was conducted.First,this paper introduces the research status of the numerical simulation of circulating fluidized bed boilers and combustion at home and abroad.Then the information collected by the boiler plant is combined with its own actual conditions.The simulation model was designed for the selected type of boiler and model parameters were selected,and the calculation model and the input variables of the furnace reaction are determined.Then,boiler model is subjected to the combustion numerical simulation experiment under the change of standard operating conditions and input variables.Based on the experimental results obtained,the gas flow in the furnace during combustion of the boiler,as well as the distribution of temperature,component gas content,and particle trajectory are described;the influence of different parameter settings on the boiler combustion under standard conditions was analyzed;which verified the rationality of the combustion numerical simulation on the model.Finally,a multivariate curve fitting study was performed on the input variables and fuel burnout rates during numerical simulation of model combustion by the range of optimum combustion conditions under standard conditions derived from numerical simulation results,and the functional relationship between the input variables and the burnout rate was determined,and the reliability of the fitting formula was verified.The reference values of the optimal combustion conditions under normal conditions are given.At the same time,the fuel burnout ratios before and after the change of the boiler model parameters are compared,thus confirming the rationality of the boiler plant's optimization and design of the actual boiler model structure.