超超临界机组发电技术在我国已经十分成熟,但众多机组参与新能源并网的调峰计划时仍面临变负荷运行与低负荷稳燃的难题,其中水冷壁的壁温控制是确保锅炉安全运行的关键。流量分配与壁温计算方法是评价水冷壁特性计算模型的主要标准,Ebsilon16.4基于德国的VDI热力计算标准对热力系统的仿真有着精细且全面的优点,适合研究锅炉受热面—尤其是水冷壁的热物理特性。在锅炉系统仿真的基础上,针对水冷壁不同区域的管路、鳍片与受热等区别,将水冷壁分为冷灰斗、螺旋管与垂直管三个部分计算分析,该方法避免了水动力计算方法所需的高精度建模与回路的有限元划分,在系统层面上获取具有鲜明特征的水冷壁区块特性,包括平均换热量、平均金属壁温与平均热流密度。在此基础上,通过改变水冷壁压力、温度与质量流量,分析水冷壁特性的变化趋势,与电厂的实际工程数据进行对比,证明通过热力系统仿真的方式获取不同区域的水冷壁特性是可行的。

The power generation technology of ultra-supercritical units has been very mature in our country, but many units are still faced with the problem of variable load operation and low load steady combustion when participating in the peak regulation plan of new energy connected to the grid. The wall temperature control of water cooling wall is the key to ensure the safe operation of boilers. Flow distribution and wall temperature calculation method are the main criteria for evaluating the calculation model of water wall characteristics. Ebsilon16.4 is based on the German VDI thermal calculation standard, which has the advantages of fine and comprehensive simulation of thermal system, and is suitable for studying the thermal physical characteristics of boiler heating surface, especially the water wall. Based on the simulation of the boiler system, the water wall is divided into three parts, namely cold ash hopper, spiral tube and vertical tube, according to the differences of pipes, fins and heating in different areas of the water wall. This method avoids the high-precision modeling and finite element division of the loop required by the hydrodynamic calculation method, and obtains the block characteristics of the water wall with distinctive characteristics at the system level. It includes average heat transfer, average metal wall temperature and average heat flux. On this basis, by changing the pressure, temperature and mass flow of the water wall, the variation trend of the water wall characteristics is analyzed, and the comparison with the actual engineering data of the power plant proves that it is feasible to obtain the characteristics of the water wall in different regions by means of thermal system simulation.

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中国南方电网公司重点项目:燃煤机组深度调峰下稳燃机理及水动力安全关键技术研究(NYJS2020KJ005)；国家自然科学基金重点项目(51376161)