In general:
Device, which reduces the pressure (pulsation) fluctuations and therefore reduces the noise produced in connection with this, without preventing the transport of the fluid.
In hydraulics:
The silencer is intended to reduce the pressure fluctuations in the line downstream of the pump. To operate in the widest possible frequency range, the effects of the entire system must be considered, i.e. such a silencer must be adapter to the respective system. This is a common failure.
When working primarily with reflective silencers with an expansion chamber,
in which the primary sound wave is extinguished by a second wave of the same amplitude and frequency, but with a phase position shifted by 180° (Figure S 5).
The success of the silencer in hydraulic systems is impaired by the fact that its optimal efficiency is limited to a few frequencies, but the pressure pulsations of pumps comprise a relatively broad spectrum. In addition, the most favourable installation location must be redefined for each system.
Figure S 5: Construction types of reflective silencers