An Optimized Lightweight Ultrasonic Liquid Level Sensor Adapted to the Tilt of Liquid Level and Ripple

Ultrasonic liquid level measuring technology has been extensively applied in the industrial field, which is characterized by its high accuracy, strong ability of anti-electromagnetic interference and simple structure. However, its measurement results are easily affected by the tilt of liquid level and ripple. In this study, the traditional gas-liquid interface was transformed into a solid-liquid interface based on the acoustic scattering by a rigid sphere and a circular waveguide, and the liquid level was measured with the stable reflecting surface by complying with the liquid level in the duct. Such a method could overcome the effect of the tilt of liquid level and ripple on the measurement results. In this study, a signal processing method to improve the signal to noise ratio of the direct wave was proposed. To improve the sound intensity of the direct wave and reduce the effect of high-order mode waves on the signal, the transceiver was applied with a matching layer, and the appropriate waveguide material should be selected to absorb a portion of high-order mode waves. As revealed from the experimentally achieved results, an optimized lightweight ultrasonic liquid level sensor was proposed to eliminate the effect of ripple, and the tilt of liquid level increased from 20° to 60°.