【摘要】 在将裂纹板挠度表示为正交多项式之和的基础上,利用瑞利 里兹方法,求解了周界固定径向裂纹板的低阶振动模态频率及挠度;进而利用瑞利积分,求解了裂纹圆板自由振动辐射声场的轴向声压分布及距板心50cm球面上声场的指向性,并与完整板的辐射声场作了对比.用撞击法测定了裂纹圆板辐射声场的频谱,结果与理论值及有限元法求得的结果基本符合.更多还原

【Abstract】 Based on the deflection of a circular plate with a radial crack is expressed as the summation of orthogonal polynomials, the frequencies and deflections of low modes of the cracked circular plate clamped on the edge are solved by RayleighRitz method, and then by using Rayleigh integration the axial pressure distribution of the sound field radiated by the free vibration circular plate and the sound directivity pattern at distance 50cm from the center of the plate are presented. These results are compared with the sound field radiated by an unbroken circular plate. Experimentally the spectra of the sound field are measured by using collisionexcited method, and the frequencies are in good agreement with theoretical and FEM results.更多还原