THE CANCELLING OF VIBRATIONS TRANSMITTED THROUGH A FLUID IN A CONTAINING VESSEL

摘要

Method of and apparatus for reducing the vibration (e.g. noise) transmitted into the environment of a fluid-containing vessel by a vibration source within the vessel. The invention relies on an "active" attenuation method in which a specially tailored cancelling vibration is applied to the fluid in the vessel, whereby at least partial cancellation of the vibration from the source occurs within the fluid. The invention has particular application to reducing the environmental noise nuisance caused by the core (2) in an oil-filled transformer tank (1), a vibrator (7) being energised by a waveform generator (8) and injecting the cancelling vibration into the oil (3) via a diaphragm (5). The output from vibration sensors (Mu....Mu) can be used to control the generator (8), The invention can also be applied to pumps and fluid filled pipes.