Design And Development Of Household Water Flowmeter Based On Ultrasonic Technology

At present, most household water flowmeters in our country is Mechanical rotor-type, but this type of water meters have high leakage ratio, fast wearing, and low precision. In order to meet the goal of saving water, a sort of flowmeter for the household water measurement based on the ultrasonic technology is designed. The water meter should have higher accuracy than mechanical ones, and have simpler operation and lower cost.In this paper, the transit-time-difference method is adopted to measure the water flux. The emitter-receiver dual-use piezo-ceramics ultrasonic transducer is selected as the flow measurement sensor with the central frequency of 1 MHz and the ultrasonic transducer channel layout is designed. In order to get good ultrasonic signals, the ultrasonic transducer driver module and the signal processing module are designed, which uses the zero-crossing detection method and the software shielding window as the core. The time-counting modular circuit, whose function is to measure the transit-time accurately, is designed with a time-converting chip with high precision. As for the software part, the main work is data processing and display of the results as well as setting and modification of relevant parameters.Finally, many experiments are carried out to test the flowmeter, and the results show that the error of the ultrasonic flowmerer achieves±1%. It is obvious that the accuracy of the instrument designed in this paper is higher than the mechanical ones. The instruments we designed meet the design requirement.