四边简支弯曲振动方形薄板辐射阻抗及辐射声功率的研究

Radiation Impedance and Acoustic Radiation Power of the Simply Four-side-supported Square Thin Plate in Flexural Vibration

从振速分布不均匀振动面辐射阻抗的定义出发,推导了不同模态的四边简支方形薄板以中心点振速为参考的辐射阻抗表达式,研究了弯振方形板辐射阻抗对辐射声功率的影响。结果表明:对于四边简支方形薄板,当中心点振速一定时,在中低频段,模态越低,对应的辐射阻越大,因而辐射声功率也越大。四边简支的弯振方形板的辐射声功率主要由其低模态的声功率决定。

The author starts from the definition by Professor He, and deduces the radiation impedance of the flexural vibration square plate in the condition of supporting boundary in different modality, which takes the center point velocity as the reference. How the radiation impedance influences the sound power is studied in this paper. It can be shown from the results that When the center point＇velocity is certain in the square plate in the condition of supporting boundary, the lower the modality of the vibration is , the greater the radiation resistance is , and so is the sound power. The radiation sound power of the flexural vibration square plate in the condition of supporting boundary is decided mainly by the sound power of the lower modality.