摘要
采用能量法研究了不同温度梯度下功能梯度材料圆柱壳的热屈曲行为.屈曲临界条件由里兹法得到;由于材料属性和温度的耦合效应,临界温升通过迭代算法求得.讨论了两种温度梯度形式以及物性温度相关性对临界温升的影响.数值结果表明:功能梯度材料的组分参数只在一定小范围内对临界温升有显著影响,而结构尺寸参数对其影响较大;在功能梯度材料圆柱壳热屈曲分析中必须考虑物性温度相关性,否则将高估临界温升;若采用抛物型温度场来代替实际的热传导温度场,临界温升在陶瓷含量较多且壳厚较小的情况下,将可能被低估,而在金属含量较多且壳厚较大的情况下,却可能被高估.
The thermal buckling behaviors of functionally graded cylindrical shells subjected to temperature gradients are investigated by using the energy method. The critical buckling condition is given by employing the Ritz method. Due to the coupling effect between material properties and temperature field, the critical temperature rise is obtained via an iterative algorithm. Moreover, the effects of two kinds of temperature gradients and temperature-dependent material properties on the critical temperature inhomogeneous parameter of functionally graded materials rise are discussed. Numerical results show that (1) the affects the critical temperature rise significantly only in a small scope ; (2) the effect of structure dimension on the critical temperature rise is greater than that of the inhomogeneous parameter; (3) the temperature-dependent properties must be considered in the thermal buckling analysis of functionally graded cylindrical shells, otherwise the critical temperature rise would be overestimated; and (4) if an assumed quadratic distribution is used to approximate the actual steady one-dimension thermal conduction, the critical temperature rise is likely to be underestimated in the condition of ceramic-rich thin shell, while being over- estimated in the condition of metal-rich thick one.
出处
《华南理工大学学报(自然科学版)》
EI
CAS
CSCD
北大核心
2009年第6期101-106,共6页
Journal of South China University of Technology(Natural Science Edition)
基金
国家自然科学基金资助项目(10672059)
广东省自然科学基金资助项目(8151064101000002)
关键词
功能梯度材料
圆柱壳
热屈曲
物性温度相关性
温度梯度
functionally graded material
cylindrical property
temperature gradient shell
thermal buckling
temperature-dependent material