Making use of turbulence and its interaction with sound: a non-invasive flow monitor

Abstract

A novel acoustic sensor has been developed which is capable of remotely monitoring the free surface ‘fingerprint’ of shallow flows. The temporal and spatial properties of this fingerprint are shown to contain a wealth of information regarding the nature of the flow itself. The remote measurement can thereby be used to infer the bulk flow properties such as depth, velocity, and hydraulic roughness to within 8 % accuracy. The instrument is totally non-invasive and as such is low cost, low maintenance, and low power. Such a device will allow for widespread monitoring of flow conditions in drainage and river networks, informing flood models, and facilitating pro-active maintenance and real time control.