基于风门调节特性仿真的二次风调平技术

Technology for secondary air equalization based on the turning performance simulation of air damper

二次风调平是保证锅炉良好燃烧组织的主导因素。现有的调平技术普遍存在测量误差大、试验能耗高、劳动环境恶劣和工期受限严重的问题,调平效果远不及设计预期。通过建立二次风喷口及其风门的流体仿真模型,拟合模型计算结果,获得了风门的调节特性,即阻力系数与风门角度之间的定量关系。在确定的风量相对偏差允许范围内发现,风门角度越大,风门角度偏差的允许范围也越大。据此开发了在不通流条件下,定量检查和评价二次风门状态的技术。该技术用倾角测量替代风速测量,并将风量偏差转换为风门角度偏差。在某600 MW亚临界锅炉的试验结果表明,该技术可实现二次风门调节特性的安全、准确、高效、低成本检测,并能及时指导设备消缺,确保二次风均匀性与设计相符。

The secondary air equalization is the prominent factor of good combustion organization in boiler.The former technology of secondary air equalization encounters many problems,such as large measurement error,high test energy consumption,bad working environment and rigid test time,which cause obvious departure from expectation.The turning performance of secondary air damper was studied by establishing the fluid simulation model of the secondary air system,and represented with the quantitative relationship between the resistance coefficient and the damper angle.The result shows that the greater the damper angle is,the greater the damper angle allowable error is,within the certain allowable error of air flow.Furthermore,a novel checking and assessing technology for turning performance of the secondary air damper is developed,independent of air flow.The two characteristics were created,checking damper angle instead of the air flow rate,and assessing the damper angle error instead of the air flow rate error.The proof test was conducted on a 600 MW subcritical boiler.This technology checks and assesses turning performance of the secondary air damper safely,accurately,efficiently and economically.Incorporating with the effective defect elimination,the secondary air equalization can fit the expectation well.