The proper selection and sizing of the silencer is of utmost importance to ensure that pressure drop, acoustical performance and other specific design criteria are met.
The selection of the correct type of engine intake and exhaust silencer is determined by the type of engine, the end use of the engine and the degree of silencing required.
Also, the silencer size selected must accommodate the specified volume of exhaust gas flow, keeping the back pressure within the limits specified by the engine manufacturer.
The attenuation curves shown for each model indicates the insertion loss in dB at different frequencies. These curves represents the expected dynamic insertion loss at each frequency using the respective silencer.
The resultant silenced noise levels may vary to some extent as many factors influence the silenced noise which indudes the engine size, type, speed, unsilenced noise levels and frequency distribution.
These curves represents the insertion loss for airborne noise only and has no bearing on structure borne mechanical noise or pipe radiated noise. Therefore these curves can be used as a guide line only for evaluating the total system.