Self-excited vibration of a perforated plate installed in a pipe

摘要

The pressure fluctuation caused by a ring vortex shedding from a perforated plate with holes installed in a pipe was investigated experimentally. A 3.0 mm thick brass perforated plate with 30 holes with diameters of 3.0 mm was tested. Pressure fluctuations and plate vibrations were measured using pressure tranducers and strain gages, respectively, at Reynolds numbers from 6.77x10~3 to 2.87x10~4 based on the velocity at the hole. When a lock-in phenomenon occurs, the amplitude of the pressure fluctuation increases markedly. the perforated plate is subjected to an in-phase lateral vibration, which has a phase lag with respect to the differential pressure across the plate. The pressure mode shapes in the pipe agree well with those calcualted using the condition of continuity at the plate location. It was also found that these results show a pronounced similarity to the pressure fluctuation caused by the lateral vibration of the perforated plate excited axially by a piezoelectric element.