为探究某复合材料夹芯圆柱壳的振动特性,采用单点拾振法进行模态试验,并基于有限元方法对该圆柱壳进行了固有频率计算.将实验和仿真对比,发现有限元计算固有频率和实验最大误差为10.65%,模态振型大体一致,振幅曲线吻合较好.基于有限元法研究了长度 、半径以及芯材表层厚度分布对该圆柱壳基频的影响,结果表明:长度和半径的增加均导致基频的降低,但长度的变化对基频的影响更显著;圆柱壳基频状态时的振型与几何参数有关,即半径增加,环向波数增多;长度增加,环向波数减少.采用二阶实体单元对芯材进行离散,内外表层相对中面线位移具有对称性,芯材因其自身的弹性处于压缩状态,说明有限元法能有效模拟内外表层横向位移运动情况.%In order to investigate the vibration performance of composite sandwich shells ,model ex-periment with single point pick-up method is carried out and the finite element method is applied to calculate the natural frequency .The comparison between the experiment and the simulation shows that the maximum error of calculated natural frequency is 10 .65% and vibration modes and amplitude curves are in good agreement .Based on the finite element method ,the parametric study is also made to investigate the effect of geometrical properties such as radius of cylindrical shell ,length and the thickness distribution of face and core .The results indicate that increasing the radius and the length of the shell leads to decreasing the natural frequency of the shell and the length has the predominant effect .Increasing the radius leads to increasing the circumferential wave number ,while increasing the length leads to decreasing the circumferential wave number .Second-order solid element is applied to discrete the core .The results show that there is symmetry in the displacement of top and bottom faces and the core is compressed for its own elasticity ,which indicates that FE method can model the real movement of top and bottom faces .
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