外层蒙皮加强充水气囊圆柱壳的声辐射

为降低充水加肋圆柱壳受内部点声源激励时的辐射噪声,在其外表面整体敷设了气囊式声学覆盖层.气囊式声学覆盖层由内外层橡胶蒙皮与内部充入的气体组成,并在外层蒙皮中嵌入一层较薄的铝质芯板或在外层蒙皮中嵌入等间距的钢丝环.采用声无限元法,计算敷设气囊式声学覆盖层的充水圆柱壳的水下辐射噪声,结果表明采用铝板加强外层蒙皮的气囊式声学覆盖层可以降低充水气囊圆柱壳的水下辐射噪声,而采用钢丝环加强外层蒙皮则不能够降低充水气囊圆柱壳的水下辐射噪声.

Noise and vibration reduction effects of gas-bag coating stiffened by steel wires

A gas-bag is coated on the cylindrical shell in order to reduce its vibration and radiated noise when excited by force. The gas-bag coating consists of the inner and outer coating and the gas filled in, with the outer covering built in a very thin aluminum layer or steel wire rings. The acoustic infinite element method (IEM) is adopted to calculate theunder-water radiated noise of the gas-bag coated cylindrical shell. Results show that the gas-bag coating stiffened by the aluminum layer can reduce the underwater radiated noise of the water-filled gas-bag coated cylindrical shell in lower bands, while the gas-bag coating stiffened by steel wire rings can't reduce the radiated noise of the gas-bag shell.