球形封头开孔接管结构屈曲特性研究  

Research on buckling characteristics of spherical head with nozzle structure

作　　者：董乃逸 贺小华[1] DONG Naiyi;HE Xiaohua(School of Mechanical and Power Engineering,Nanjing Tech University,Nanjing 211816,China)

机构地区：[1]南京工业大学机械与动力工程学院,南京211816

出　　处：《压力容器》2021年第1期38-46,共9页Pressure Vessel Technology

基　　金：国家自然科学基金项目(51675260)。

摘　　要：针对外压作用下球形封头开孔接管结构,采用有限元非线性屈曲分析方法,探讨不同结构参数对其临界失稳压力P cr的影响。研究结果表明,当球壳主体参数径厚比一定时,临界失稳压力削弱系数K随开孔率增大而下降,随接管与封头厚度比增大而增大。接管与封头厚度比较小时,计算模型失稳位置位于接管;接管与封头厚度比增至一定值时,计算模型失稳位置转移到封头。随着开孔率增大,失稳位置由接管与封头转到封头所需的接管与封头厚度比越大。针对本文计算参数,提出了临界接管与封头厚度比。实际工程设计中,当接管与封头厚度比取临界值时,可以在满足结构轻量化设计基础上,获得较优的结构承载能力。最后,建立了不同结构参数与临界失稳压力削弱系数K的分段经验关系式,且所得关系式具有较高预测精度。研究结果可为外压球形封头开孔接管结构稳定性研究及工程设计提供借鉴。For the spherical head with nozzle structure under external pressure,the finite element nonlinear buckling analysis method was used to discuss the influence of different structural parameters on its critical buckling pressure P cr.The results show that when the diameter-thickness ratio is constant,the weakening coefficient K of critical buckling pressure decreases with the increase of opening ratio and increases with the increase of nozzle-head thickness ratio.When the nozzle-head thickness ratio is small,the instability position of the calculation model is located at the nozzle;while the instability position of the calculation model shifts to the spherical head when the nozzle-head thickness ratio increases to a certain value.With the increase of the opening ratio,the thickness ratio of the nozzle and the head is larger when the instability position shifts from nozzle to spherical head.The critical nozzle-head thickness ratio is proposed in view of the calculation parameters in this paper.In practical engineering design,when the nozzle-head thickness ratio is taken as the critical value,the optimal bearing capacity can be obtained on the basis of satisfying the lightweight design of the structure.Finally,the empirical relations between the weakening coefficient of critical buckling pressure and different structural parameters were established,and have high prediction accuracy.The research results provide reference for structural stability research and engineering design of spherical head with nozzle structure under external pressure.

关 键 词：球形封头 开孔接管 屈曲性能 临界失稳压力 

分 类 号：TH49[机械工程—机械制造及自动化] TQ050.3[化学工程]