Particle Counter for Sediment Transport Studies

An acoustic instrument for the measurement of the mass transport of sand-sized sediment particles in laboratory and natural transport systems has been developed. The instrument consists of an electromechanical transducer for the detection of sediment particles entrained in a moving fluid (air or water) and an electronic circuit which counts the transient signals produced when particles impact the transducer. By virtue of the principle of detection, instrument response to fine-grained sediment (silt and clay) and low-density material is negligible. Laboratory tests and field experiment conducted in a sand-bedded stream demonstrate that the instrument responds systematically to the mass flux of particles and therefore is potentially useful for investigations of bedload transport. The instrument is best suited for studies of transport systems characterized by high transport rates and flow velocities and having well-sorted bed material.