摘要
针对熔盐堆用冷冻法兰使用时中心孔处应力较大、易出现裂纹等问题,提出在法兰内部嵌入阻热环的结构优化方案(阻热环由纯镍包覆,内部填充导热系数很低的气凝胶),以期降低法兰的温度梯度从而降低应力。探究法兰颈部厚度对法兰密封处温度和最大应力的影响,以及拉伸方向(法兰接管方向和径向)对法兰最大应力的影响,以期在降低法兰应力的基础上降低法兰的质量和尺寸。采用有限元法计算法兰的温度、应力及蠕变疲劳损伤。结果表明:法兰内置阻热环可降低温度梯度,进而降低法兰应力;法兰密封处的温度和应力随法兰颈部厚度的减小而降低;沿接管方向拉伸法兰可降低法兰最大应力。最终优化方案中法兰的质量、尺寸大幅下降,减重效果明显,满足ASME NH高温评定要求。
To reduce the temperature gradient of the flange and thus reduce the stress,a structural optimization scheme is proposed to embed a heat-resistant ring inside the flange(the thermal heat-resistant ring is covered by pure nickel and filled with aerogel with very low thermal conductivity)for the problems such as high stress at the center hole and easy to develop cracks when the freeze flange for molten salt pile reactor is in use.The effect of flange neck thickness on the maximum stress at the flange seal and the temperature,and the effect of tensile directions(flange receiver direction and radial direction)on the maximum stress of the flange were investigated to reduce the mass and size of the flange based on the reduction of flange stress.The temperature,stress and creep fatigue damage of the flange were calculated by the finite element method.The results show that the built-in thermal heat-resistant ring of the flange can reduce the temperature gradient and thus reduce the flange stress,the stress at the flange seal and the temperature decrease with the reduction of the flange neck thickness and stretching the flange along the receiver direction can reduce the maximum flange stress.The mass and sizes of the flange in the final optimized solution are significantly reduced,and the weight reduction effect is obvious,meeting the requirements of ASME NH high temperature assessment.
作者
范金辉
孙锦涛
解明强
陈庆标
樊辉青
王猛
张健宇
傅远
梁建平
FAN Jinhui;SUN Jintao;XIE Mingqiang;CHEN Qingbiao;FAN Huiqing;WANG Meng;ZHANG Jianyu;FU Yuan;LIANG Jianping(College of Mechanical Engineering,Donghua University,Shanghai,China;Shanghai Institute of Applied Physics,Chinese Academy of Sciences,Shanghai,China;Zhejiang Jiuli Hi-Tech Metals Co.,Ltd.,Huzhou,Zhejiang,China)
出处
《东华大学学报（自然科学版）》
CAS
北大核心
2024年第5期94-101,共8页
Journal of Donghua University(Natural Science)
基金
国家重点研发计划(2021YFB3700602)
浙江久立特材股份有限公司“熔盐环境用冷冻法兰合作开发”(2020YF174)
关键词
冷冻法兰
熔盐堆
应力评定
结构优化
有限元分析
freeze flange
molten salt reactor
stress evaluation
structure optimization
finite element analysis
