Understanding Noise Vibration Control 噪声与振动控制.pdfVIP

Understanding Noise Vibration Control 了解噪声与振动控制 Type of Noise 噪声的类型 • There are 2 types of noise: – Air-borne noise 空气传播的噪音 – Structure-borne vibration, which will appear as airborne noise after being radiated by a structure 结构传播的振 动辐射出了空气噪声 Control of Noise Vibration 噪声与振动控制 • Noise and Vibration can be controlled by using four methods 噪声和振动可以用四种方法控制: – Barrier 屏障 – Absorption 吸收 – structural damping 结构阻尼 – vibration isolation 振动隔离 Control of Noise Vibration 噪声与振动控制 • In general, combined methods are used for effective noise control 一般情况下，需用组合方法来达到有效的噪声控制 – Control of Air-borne Noise 空气传播噪音控制 • use both barriers and absorbers 使用屏障和吸收方 法 – Control of Structure-borne Noise 结构噪声的控制 • Use both isolation and damping 使用隔离和阻尼 Control of Air-borne Noise 空气噪声的控制 Barriers and Enclosures 障碍和外壳 • a solid material which, by virtue of its mass, acts as an acoustical reflector 固体材料凭借其质量作为声学反射体； • it is not the stiffness of the barrier that produces the noise reduction, but the mass (kg/m2) 它不是因为其刚度产生噪声屏障的，是它的质量 Control of Air-borne Noise (cont’) 空气噪声的控制 Barriers and Enclosures 障碍和外壳 • useful in reducing