摘要
以某台300 MW控制循环锅炉为研究对象,对影响水冷壁流量偏差的主要因素进行了数值分析。利用燃烧检测系统获得的炉内烟气三维温度分布和炉膛辐射能信号,计算壁面热流分布。以实际热负荷偏差为边界条件,应用数值模拟的方法研究水冷壁热负荷、汽包压力、给水比焓、循环泵增压以及上升管管径等锅炉的运行参数和结构参数对流量偏差的影响。模拟结果表明:上升管管径对流量偏差的影响最大,其次为汽包压力和壁面热负荷;上升管管径存在最优设计值,在该管径条件下,锅炉可以适应运行参数的变化,保持较好的水循环状况;此外,当锅炉结构参数确定时,机组在较高汽包压力、较低给水比焓以及适中大循环泵增压的工况下运行,流量偏差小,有利于水循环。
With a 300 MW controlled circulation boiler serving as an object of study,a numerical analysis was conducted of the main factors affecting the flow rate deviation in water walls.Three-dimensional furnace flue-gas temperature distribution and furnace radiation energy signals obtained by the use of a combustion detection system were utilized to calculate wall-surface heat-flux distribution.With the actual deviation in thermal loads serving as boundary conditions,a numerical simulation method was adopted to study the effect of boiler operational and structural parameters on the deviation in flow rates.Such parameters include thermal load of water walls,boiler drum pressure,specific enthalpy of feedwater,boost pressure of circulating pumps and tube diameter of risers etc.The simulation results indicate that the diameter of the risers has the greatest influence on the deviation in flow rates followed by boiler drum pressure and wall-surface thermal loads.The diameter of the risers has an optimum design value.Under the condition of such a diameter,a boiler can adapt to any changes in operational parameters,maintaining a comparatively good water circulation state.Moreover,when the structural parameters of a boiler have been determined,the boiler unit can secure a small deviation in flow rates favorable to water-circulation while operating under the condition of a relatively high boiler drum pressure,relatively low feedwater specific enthalpy and moderately high boost-pressure of circulating pumps.
出处
《热能动力工程》
EI
CAS
CSCD
北大核心
2006年第5期456-460,共5页
Journal of Engineering for Thermal Energy and Power
基金
国家自然科学基金资助项目(50546021)
关键词
控制循环锅炉
锅炉水冷壁
循环泵
流量偏差
数值分析
controlled circulation boilers,boiler water wall,circulating pump,deviation in flow rates,numerical analysis
