| 摘要 |
The device includes two antennae (2,3), one for the liquid phase and one for the gaseous phase of a fluid (S) flowing through a pipe (1). Each antenna is made up of a number of piezoelectric elements (2i,3i) which can emit ultrasound waves at two different frequencies (f1,f2). The antennae convert electrical signals into mechanical vibrations. The backscattered ultrasound waves are collected by the same antennae. Each element of the antennae is connected via a multiplexer (5,6) to a sinusoidal voltage generator (4,4). A demodulator (8,8) receives the backscattered signal and sends it to a processor (9) which controls the device and processes the signal. <IMAGE> |
