【摘要】 以集总参数法为基础,建立了超临界循环流化床锅炉水冷壁动态特性的数学模型,并进行二次建模,得到了能够直接用数值积分法求解的动态方程组.开发了动态特性仿真程序,该程序能对不同负荷工况下,当燃料量、汽轮机进口阀门开度、给水流量与温度发生扰动时的水冷壁动态特性进行计算,为锅炉设计和安全运行提供了依据.对我国自主开发的1台600 MW超临界循环流化床(CFB)锅炉,在30%锅炉最大连续蒸发量(BMCR)和100%BMCR负荷工况下,当流量、压力、进口焓值、热负荷发生变化时的水冷壁动态特性进行了计算,得到过冷段长度、压力、出口焓值、工质温度与金属壁温的响应特性.结果表明:在扰动发生一段时间后,响应参数均趋于稳定不变,说明流动系统是稳定的,水冷壁设计和运行是安全可靠的.更多还原

【Abstract】 A mathematical model for the dynamic characteristics of the waterwall of the supercritical circulating fluidized bed(CFB) boiler was established on the basis of lumped parameter method.The second-time modeling was carried out,and the dynamic equation group which can be solved directly by numerical integration was derived.The simulation program for the dynamic characteristics was developed,which can calculate the dynamic characteristics of the waterwall response to step changes in fuel flow rate,the opening of the inlet valve of the steam turbine,flow rate and temperature of feed water at different load conditions,offering reference for boiler design and safe operation.The response characteristics of hot water section length,pressure,outlet enthalpy,working medium temperature and metal wall temperature of the waterwall of a self-developed 600 MW supercritical CFB boiler were derived when the flow rate,pressure,inlet enthalpy,heating load was changed at 30% of BMCR and 100% of BMCR load.Results show that the response parameters tends to be stable in some time after the disturbance occurs,which indicates that the flow system is stable,and the design and operation of the waterwall are safe and reliable.更多还原