高温圆管轴对称导波频散特性的谱方法  

Spectral method on exploring dispersion characteristics of axially symmetric guided waves in high-temperature tube

作　　者：于保华[1,2] 杨世锡[2] 甘春标[2] 雷华[3] 

机构地区：[1]杭州电子科技大学机械工程学院,浙江杭州310018 [2]浙江大学机械工程学系,浙江杭州310027 [3]浙江大学工程力学系,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2014年第9期1668-1675,共8页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金资助项目(11172260;11072213;11072214);高等学校博士学科点专项科研基金资助项目(20110101110016);国家自然科学基金创新研究群体科学基金资助项目(51221004);国防基础科研计划资助项目(A3920133001)(该项目是涉密的);浙江省科技计划资助项目(2013C31086);中央高校基本科研业务费专项资金资助项目(2013XZZX005)

摘　　要：针对传统寻根法分析圆管导波频散特性效率偏低以及高温环境对频散特性影响的问题,基于Navier位移运动方程及材料参数的温度依赖关系,推导并建立考虑高温影响的圆管轴对称导波的频散特性方程组;运用谱方法快速高效地分析和获取导波频散特性,同时设计相应的算法流程及图形化分析程序;基于谱方法和寻根法开展常温及高温2种工况下的数值算例仿真与分析,并提出一种更易分析的"频散强度"模型.算例结果表明:2种分析方法获取的频散特性完全吻合,而谱方法分析时间明显小于传统寻根法.本研究可为高温圆管轴对称导波检测参数的优化选择及后续信号分析提供理论支持.For resolving the negative affect of dispersion and multi-mode characteristics of guide wave in tube defect detection, a single mode narrow-band guide wave should be excited through narrowband excita- tion and wavelength tuning method. The choice of guided wave excitation mode and excitation frequency relys on the guided wave dispersion characteristic curve analysis. For relieving the problem of low efficien- cy in use of traditional root-finding approach for dispersion characteristic and the impact of high tempera- ture to dispersion characteristic, the dispersion characteristic equations of the axially symmetric guided wave in tube considering the impact of high-temperature were derived based on the Navier displacement equations and the temperature-dependent material properties model. Then, guided wave dispersion charac- teristic was rapidly acquired by the spectral method, and the corresponding algorithm and a graphical user interface were also designed to facilitate the analysis. The dispersion curves of the axially symmetric guided wave were drawn from the numerical results by the root-finding approach and the spectral method at two kind temperature conditions. On one hand, data obtained bv these two methods were well matched; on the other hand, the spectral approach shows to possess higher analytical efficiency than that of the root-finding approach. The spectral approach for axially symmetric guided wave in high-temperature tube can help for detection parameter selecting and subsequent signal analysis.

关 键 词：高温圆管 轴对称导波 频散特性 谱方法 寻根法 频散强度 

分 类 号：O348.8[理学—固体力学] TG115.28[理学—力学]