本文乃是討論當平板開有孔洞時，以點聲源激振平板，分析有孔平板之振動及聲壓變化情形。 為了更進一步知道孔洞對平板振動及聲壓的影響，在平板上開四個方形的孔洞，且應用“Ectoplasm”之方法及觀念，並利用漢彌頓定理推導有洞薄方板的運動方程式，計算自然頻率並觀察其變動情形。當點聲源位於有孔平板中心且距平板高度固定時，以不同聲源頻率激振平板，然後比較其所得之位移。 在聲場方面，分析板面振動產生之輻射聲壓及孔洞所產生之繞射聲壓的影響，並引入克赫積分方程式及格林函數來處理有孔平板之輻射與繞射的相關問題，最後並比較孔洞位置、孔洞大小對聲壓之變化情形。 This paper is discusses the vibration and corresponding sound field of the holed plate excited by a point sound source. The plate is perforated into four holes in the center of symmetry. The vibration analysis is based on the technique of the “Ectoplasm”. The equation of motion of the plate is derived by the Hamilton’s principle. The dynamic response of the plate excited by a point sound source is solved. In order to deal with the acoustic field of the holed plate, the Kirchhoff-Helmholtz integral and the Green’s function are used. The sound pressure distribution of the plate is investigated with different positions of the holes.
