This investigation focuses on the modal analysis of an axially functionally graded material beam under hygrothermal effect. The material constants of the beam are supposed to be graded smoothly along the axial direction under both power law and sigmoid law distribution. A finite element analysis with COMSOL Multiphysics® (version 5.2) package is used to find the Eigen frequencies of the beam. The accuracy of the technique is authenticated by relating the results with the prior investigation for reduced case. The effects of moisture changes, temperature, and volume fraction index, length-to-thickness ratio on the Eigen frequencies are investigated in detail. It is believed that the present investigation may be useful in the design of highly efficient environmental sensors for structural health monitoring perspective.

中文翻译：

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湿热作用下轴向功能梯度材料梁的模态分析

本研究的重点是在湿热效应下轴向功能梯度材料梁的模态分析。梁的材料常数应该在幂律和 sigmoid 定律分布下沿轴向平滑渐变。使用 COMSOL Multiphysics®（5.2 版）软件包进行的有限元分析用于找到梁的特征频率。该技术的准确性通过将结果与先前针对减少病例的调查相关联来验证。详细研究了水分变化、温度和体积分数指数、长厚比对特征频率的影响。相信本研究可​​能有助于设计用于结构健康监测的高效环境传感器。