This paper describes the development of an ultrasonic flow meter using a new type of transducer called the mode coupling transducer (MCT). The mode coupling transducer consists of a thin plate of a suitable piezoelectric material on which an interdigital transducer (IDT) is deposited for the generation and detection of plate acoustic waves. The flow meter consists of two such transducers mounted on opposite walls of a pipe through which the fluid is flowing. The transducers used in this work were fabricated on 0.5 mm thick plates of lithium niobate and had a center frequency of 1 MHz. The prototype device developed here can measure flow rates over a range from less than 0.2 lpm (liters per minute) to greater than 100 lpm.

本文介绍了使用称为模式耦合换能器 (MCT) 的新型换能器开发超声波流量计。模式耦合换能器由合适的压电材料薄板组成，其上沉积有叉指换能器 (IDT)，用于产生和检测板声波。流量计由两个这样的传感器组成，它们安装在流体流经的管道的相对壁上。这项工作中使用的换能器是在 0.5 毫米厚的铌酸锂板上制造的，中心频率为 1 MHz。这里开发的原型设备可以测量从小于 0.2 lpm（升每分钟）到大于 100 lpm 的流量。