正交各向异性C/SiC复合材料板的模态密度辨识
Modal density identification of orthotropic C/SiC composite plate

为研究C/SiC复合材料的模态密度获取方法并提高其模态密度辨识精度,以正交各向异性C/SiC复合材料板作为研究对象,在薄板理论基础上推导了正交各向异性复合材料板的模态密度理论计算公式;同时,基于点导纳法对正交各向异性C/SiC复合材料板开展了模态密度试验测试研究,并分析了附加质量对试验测试结果的影响.结果表明,对于给定的正交各向异性C/SiC复合材料板,其模态密度理论计算结果是一个定值;附加质量在中高频段对于C/SiC复合材料板模态密度测试结果影响较大;理论计算值与经过附加质量修正后的试验测试结果在中高频段吻合较好;理论解析计算及试验测试方法在进行C/SiC复合材料板模态密度辨识时具有较高的精确度.
To study the modal density acquisition method of C/SiC composites and improve its modal density identification accuracy, an orthotropic C/SiC composite plate was taken as the research object and the modal density theoretical formula of the orthotropic composite plate was derived based on the thin plate theory. In addition, the point admittance method was used to carry out the experimental study on the modal density of the orthotropic C/SiC composite plate, and the effects of added mass of sensors on the experimental results were analyzed. The results show that for the given orthotropic C/SiC composite plate, the theoretical calculation results of modal density is a determined value. Added mass of sensors has great influence on the experimental results of modal density in the medium-high frequency band for C/SiC composite plates. The theoretical value fits well with the experimental results after the correction of added mass in the medium-high frequency band. The theoretical analysis calculation and experimental testing methods exhibit high accuracy for the modal density identification of C/SiC composite plate