余热锅炉旁路挡板门壳体尺寸优化研究

Size optimization of diverter damper shell of bypass system of heat recovery steam generator

针对余热锅炉旁路系统大型烟气挡板门的结构轻量化及壳体振动问题,对三通烟气挡板门常用薄板加筋结构进行了研究。结合相关规范及实际经验,对烟气挡板门的设计工况进行了分析,提出了以加强筋H型钢截面尺寸为变量的多工况多种分析类型的数学优化模型;运用OptiStruct优化软件,对壳体加强筋进行了尺寸优化分析,主要涉及静力强度分析、模态分析和屈曲分析;结合常用H型钢型号,经过重新计算验证,最终给出了优化后的H型钢截面尺寸。研究结果表明:优化后该结构强度、刚度和屈曲满足规范要求,2阶振动频率由6 Hz降低为5.19 Hz,满足燃机避免共振要求;加强筋H型钢较设计前减重约30 T。

Aiming at the light weight and vibration problem of diverter damper of bypass system of heat recovery steam generator(HRSG), the study on plate with stiffener of tee diverter damper were carried out. Combined with the relevant standards and practical experience, the design and analysis load of diverter damper were summarized. Multiple load condition and analysis type of the mathematical optimization model which taken the stiffener H-beam section size as variable was established. The size optimization analysis of the shell stiffener of bypass damper was carried out with the help of OptiStruct software, which mainly involves static strength analysis, modal analysis and buckling analysis. The optimized H-beam section size was finally obtained after re-calculation and verification. The results indicate that the strength, stiffness and buckling of the structure after optimization meet the standard requirements, and the 2-order vibration frequency is reduced from 6 Hz to 5.19 Hz, meeting the requirement of avoiding resonance of gas turbine. Reinforcing stiffener is about 30 T lighter than the design before.