Reduction of Noise in Roots Blower

抄録

A new casing has been devised, in order to reduce the noise of Roots blowers caused by their unique compression process. With an extended peripheral length, the new casing gradually reverses the flow of a high pressure gas on the discharge side through the clearance between the casing and the tip of the rotor. Using a 5.5kW Roots blower, a comparative test was made between the conventional casing and this peripharal extended casing having a clearance that should cause the pressure in the closed suction chamber to rise sinusoidally. As a result, it was found that the new casing could help mitigate the pressure pulsation of a discharge gas to reduce the discharge noise by about 10 dB(A).