Ultrasonic multiple-sensor solid level measurements

Ultrasonic level measurement technique is a well established field finding path in many industrial applications. While the method works well on liquid level measurements, they are not as reliable and accurate in solid level applications. A simulation technique using Huygen´s principle, Snell´s law and Descarte´s law clearly illustrates the physical reasons behind the incorrect operations of such devices when applied to solid filled bunkers. The distortions, scattering, folding and directional propagations of ultrasonic energy occur causing errors. The shapes of the containers, the surface profiles, the depth of solids and the propagation angles of the beam are the main factors in determining the reliable and correct operations. However, as demonstrated in this paper, the distorted and directional returning waves can be picked-up by multiple sensors and signals can be processed suitably for improvements in reliability and accuracy