Ultrasonic transducers for measuring waterflow

Hi all,

I want to install ultrasonic sensors for detecting and eventually measuring water flow in a home 1-inch pipe.

Here is the theory

I am looking for ultrasonic transducers that I can place on the pipe. I will 3d print some clamps.

Each of the transducers (A+B) will both emit and receive. At first the transducer A will emit and B will receive. Then B will emit and A receive. The dt (time diff) will show us speed of water.

Is it possible to use HC-SR04 (after disassembling)???
Is it possible to make the HC-SR04 transducers switch roles? (emit, transmit)??


What does this have to do with Blynk?