Particle transport meter using ultrasonic technique - measures throughput of sand or sediment in water flow by phase shift detection

摘要

Echoes (m1,m2) of the ultrasonic signal produced by a transmitting transducer (T1) are caused by particles in liq. suspension and are detected by two identical piezo-electric transducers (T2,T3) placed at a fixed distance from each other. The detector outputs (S1,S2) are individually squared (1,2). The outputs are fed to a dividing circuit (3) and the divider output is then multiplied by the output of the first squaring circuit (1). If the gap between the two receiving transducers is twice the wavelength of the transmitted signal, the multiplier output is proportional to the concn. of particles in the measuring area.