Dual-Wave Doppler Digital Velocity Sensor Manual

Introduction
Using acoustic technology, it is possible to measure velocity directly using the Doppler effect.

The following table explains the ultrasonic Doppler effect.

Using the Doppler principal:

• Ultrasonic energy is continuously transmitted under water into the flow stream.
• The sound waves are reflected from tiny solid matter in the flow stream.
• The transmitted frequency is compared to particle bounce frequency.
• Thousands of velocity return signals are collected and averaged to produce representative average velocity.
• Average velocity is a function of sample time and echo reduction parameters.