排序方式: 共有4条查询结果,搜索用时 0 毫秒
1
1.
以Timoshenko单跨梁为研究对象,采用回转射线矩阵法进行动力响应计算,针对Timoshenko梁的瞬态响应信号为非平稳信号,采用基于Hilbert—Huang变换原理的信号时频分析,并与FFT的处理结果进行对比分析。结果表明,HHT方法比Frr法更适合非平稳信号的分析和处理,同时,HHT方法不仅可以将瞬态信号中低频和高频部分分离出来,还可以通过Hilbert谱展示信号能量在时频域内的分布,更为深入的了解信号的本质。 相似文献
2.
3.
Based on the Burgers equation and Manley?Rowe equation, the derivation about nonlinear interaction of the acoustic waves has been done in this paper. After nonlinear interaction among the low-frequency weak waves and the pump wave, the analytical solutions of acoustic waves’ amplitude in the field are deduced. The relationship between normalized energy of high-frequency and the change of acoustic energy before and after the nonlinear interaction of the acoustic waves is analyzed. The experimental results about the changes of the acoustic energy are presented. The study shows that new frequencies are generated and the energies of the low-frequency are modulated in a long term by the pump waves, which leads the energies of the low-frequency acoustic waves to change in the pulse trend in the process of the nonlinear interaction of the acoustic waves. The increase and decrease of the energies of the low-frequency are observed under certain typical conditions, which lays a foundation for practical engineering applications. 相似文献
4.
斜拉索风雨激振水线的超声波测试研究 总被引:7,自引:0,他引:7
斜拉索风雨激振是在风和雨联合作用下的大幅值振动,斜拉索表面水线的形成和振荡是其发生风雨激振的一个重要原因。本文利用超声波传播和反射原理,建立一套适应于斜拉索表面水线监测的超声波测试系统,对水线特征进行定量的分析研究。在风洞中再现斜拉索的风雨激振,在测量斜拉索风雨激振响应的同时,测量得到斜拉索表面水线的振荡时程,分析了水线振动幅值与平衡位置,并得到上水线振荡频率与斜拉索风雨激振的频率相等。 相似文献
1