Development of ultrasonic instrument for the sealed container’s liquid level measurement

Abstract

Ultrasonic is one of the effective methods in the field of liquid level measurement. In the process of ultrasonic propagation, reflection and refraction will occur at the interface between two different media. The reflectance ratio depends on the acoustic impedance of these two media. In this paper this property of ultrasound is used for measurement of the sealed container’s liquid level and an instrument based on a programmed software is developed. First of all the structure and the principle of operation of the system are presented. Then the transmitting and receiving circuits are described. After that the software is developed by the secondary development of the data acquisition card. And at last the developed instrument is applied to the liquid level measurement of the air-condition compressor used in the passenger train car. The instrument developed provides an effective method for the liquid level measurement of the sealed container. Since of its modular structure, the instrument can be easily transplanted to other relative fields.