LlGHTFLOW DISSIPATIVE SILENCER
APPLICATION: These silencers mostly are used in the intake or exhaust of small high speed centrifugal compressors, or in engine exhausts.
LDS silencers take the straight-through configuration, employing dissipative principles. They are constructed as concentric tubes, the inner tube perforated and the outer tube forming the shell. The gap between perforated flow tube and shell is packed with high acoustic-absorptivity material. The perforated flow tube is wrapped with glass-fibre cloth, to prevent erosion of acoustic packing into the gas stream.
Dynamic insertion loss varies across the frequency octave bands, depending on flow conditions and diameter of the flow tube. Typically, 25 - 35 dB attenuation is obtained in the 500 Hz, 1 kHz, 2kHz, and 1 kHz octave bands. Pressure drop across the silencer is slightly more than with a substitute plain tube.
These silencers are of continuously welded construction, manufactured from good quality weldable carbon steel, and finished with one coat either of red oxide primer or heat-resistant aluminium primer, depending on the operating temperature.
The silencer's plate flanges are drilled to BS10 table D. Silencers also are supplied in stainless steel or other specified material.
tandard silencers incorporate materials which can withstand the anticipated temperature extremes. Polyether froam acoustic material is used for operating temperatures up to 150°C (302°F), but long strand fibre glass is employed for operating temperatures between 150°C and 600°C (302°F and 1112°F).