船用柴油机进气消声器声学性能研究及改进设计

Research and improved design of intake silencers used in marine diesel engines

为提高某船用柴油机进气消声器的消声性能,利用有限元软件LMS virtual lab中声学模块对消声器进行了声学性能仿真研究。分析了消声器的吸声片间距、直径参数,以及吸声片两侧布置穿孔板对传递损失的影响。结果表明:吸声片间距减小2 mm,消声器的传递损失增加约2.5 d B;吸声材料外径增加40 mm,消声器传递损失在大多数频率范围内增加1~2 d B;在吸声片两侧布置穿孔板,消声效果在800~1 600 Hz频率范围内可提高约8 d B,该改进设计方案有利于抑制增压器的噪声源峰值。

To improve the acoustic attenuation performance of intake silencers for marine, the geometric model was established according to it＇s actual model. The acoustic performance of the silencer was simulated by using LMS virtual lab. The influence of the distance between sound-absorbing plates, the diameter of sound-absorbing plates and the perforated plate on both sides of silencer on the transmission loss were ana-lyzed. The results show that the transmission loss of the silencers increases by about 2.5 dB with the each 2 mm reduction in the distance between the sound absorbing plates. In most frequency range, the transmission loss of the silencer is increased by 1 to 2 dB with the sound-absorbing material for each additional 40 mm dia-meter. The acoustic attenuation performance of the improved silencer increases by about 8dB form 800 - 1 600 Hz, with the addition of perforated plates on both sides of the sound absorption plates, which is conducive to suppress the in-let noise of the turbocharger.