抄録
Orifice plates are common devices in process plant piping systems. They can be used as pulsation suppression devices for reciprocating compressor and pressure reducing devices for gas services. It is known that the restriction orifices can cause high level tone noise in certain conditions and induce severe vibrations under high pressure ratio. In this study, the properties of the sound generated at the orifice plate in piping systems were investigated experimentally. The results show that the high tone noise is generated when the orifice thickness t/d is larger than 0.5 and the frequency of flow induced noise is close to the acoustic mode in orifice hole. Sound radiation from the orifice plate is dominant in low pressure ratio condition, and flow induced noise contribute much in high pressure ratio condition. The noise level for multi perforated plate is lower than that of single hole orifice in high pressure ratio condition, while flow rate of multi perforated plate is larger than that of single hole orifice. The validity of estimation method for sound power level by process condition was shown for multi perforated plate.
