基于风粉监测的四角燃烧煤粉炉内温度场 的动态仿真模型研究

A METHOD OF DYNAMIC SIMULATION FOR TEMPERATURE PROFILE IN A FOUR-CORNER FIRED BOILER BASED ON ON-LINE MONITORING OFAIR AND COAL

针对四角燃烧煤粉炉内温度场有效监测方法的不足,提出了燃烧工况二重数值仿真思想,即在对炉内燃烧状况的离线数值模拟的基础上,通过建立炉内温度场的动态仿真数学模型,从而实现温度场的动态显示,达到对炉内燃烧状况进行监测的目的。应用某热电厂 DG130? 9.8/540 型高压煤粉炉的实际运行数据对计算模型进行了检验,结果表明:温度值的最大误差不超过 12%,说明本文提出的二重仿真理论是可靠的,基本上能满足工业应用的需要。以此为基础,开发了一套燃烧监测与诊断系统,经工业现场应用,达到了预期效果。

Considering the temperature distribution in tangential fired pulverized coal boiler is difficult to be measured and monitored, two-stage numerical simulation was put forward. First, multi-field coupling simulation for a lot of typical work conditions was carried out off-line with the software CFX-4.3, and then an expression of temperature varying with operating parameter was obtained. According to real-time operating parameters, the temperature in arbitrary point of the furnace can be calculated by using this expression. Thus temperature profile can be shown on-line and monitoring for combusting state in the furnace is realized. The simulating model was checked by the parameters measured in a operating boiler, DG130-9.8/540, and the maximum of relative error is less than 12% (maximum of absolute error is less than 120℃),which show that two-stage simulation method is reliable and able to satisfy the requirement of industrial application. Based on this method, a combustion monitoring system had been developed and applied successfully in the thermal power plant.