State Key Laboratory of Multiphase Flow in Power Engineering,Xi′an Jiaotong University

能源的可持续发展使得深度调峰成为火电发电技术中至关重要的部分,为分析深度调峰时超临界燃煤机组锅炉的灵活性改造能力及水冷壁系统的水动力安全特性,针对某350MW超临界螺旋管圈锅炉的结构特征,基于流动网格系统法,将复杂水冷壁系统划分为流量回路和压力节点,结合三大守恒定律和传热关系式建立了求解超临界锅炉水动力特性的非线性计算模型。在实炉测试的基础上,反推计算26.3%BMCR(92MW)负荷下沿炉膛宽度方向的实际吸热偏差分布,并将程序计算得出的上炉膛出口汽温和系统压降与实炉测量数据对比,验证了模型的可靠性。在实炉测试研究的基础上,分析了20%BMCR(70MW)深度调峰负荷时水冷壁的节点压力和回路质量流速分布、工质出口汽温偏差和管壁温度沿炉高方向的变化趋势,并对流动不稳定性进行校核计算。计算结果表明:该超临界螺旋管圈锅炉在20%BMCR深度调峰负荷运行时,系统总压降为0.6037MPa,上炉膛最大出口汽温偏差为29.4℃,最大外壁温度为381.1℃,最大鳍端温度为383.4℃,壁温和鳍片温度均在材料许用温度范围内,保证了20%BMCR深度调峰负荷运行时的水动力安全可靠,且流动稳定性良好。

The sustainable development of energy makes deep peaking a crucial part of thermal power generation technology. In order to analyze the flexibility modification capability of the boiler of supercritical coal-fired unit and the hydrodynamic safety characteristics of waterwall system during deep peaking, for the structural characteristics of a 350 MW supercritical spiral coil boiler, the complex water wall system was divided into flow loops and pressure nodes based on the flow mesh system method, and a nonlinear calculation model for solvingthe hydrodynamic characteristics of a supercritical boiler was established by combining the three major conservation laws and the heattransfer equation. On the basis of the real furnace test, the actual heat absorption deviation distribution along the width of the furnace at26.3% BMCR (92 MW) load was backpropagated, and the vapor temperature and pressure drop of the upper furnace exit calculated bythe program were compared with the measured data of the real furnace to verify the reliability of the model. On the basis of the real furnacetest study, the nodal pressure and loop mass flow rate distributions of the water wall, the trends of the outlet vapor temperature deviationand the wall temperature along the direction of the furnace height were studied and analyzed under 20% BMCR (70 MW) deep peakingload condition, and the calibration calculations were performed for the flow instability. Calculation results show that the supercritical spiral coil boiler in 20% BMCR deep peaking load operation, the total system pressure drop is 0.603 7 MPa, the maximum outlet steam temperature deviation of the upper hearth is 29.4 ℃ , the maximum outer wall temperature is 381.1 ℃ , and the maximum fin end temperatureis 383.4 ℃ , and the wall temperature and fin temperatures are all in the permissible temperature range of the material, which ensures safeand reliable hydrodynamics for 20% BMCR deep peaking load operation, and the flow stability is good.

国家重点研发计划资助项目(2022YFB4100303)

宋园园,郭泽瑞,安宁,等.350MW超临界锅炉低负荷深度调峰水动力实炉测试与计算分析[J].洁净煤技术,2024,30(9):33-42.

SONG Yuanyuan,GUO Zerui,AN Ning,et al.Analysis of real furnace test and calculation of hydrodynamic power for lowload deep peaking of 350 MW supercritical boiler[J].Clean Coal Technology,2024,30(9):33-42.