What is an example of a non-invasive flow meter?

The ultrasonic flow meter is an example of a non-invasive flow meter because it measures the flow of fluid without coming into direct contact with the fluid itself. It uses ultrasonic sound waves to determine the velocity of the fluid by analyzing the time it takes for sound waves to travel upstream and downstream within the flow. This method allows for accurate flow measurements without altering the fluid's composition or introducing any potential contaminants, making it highly effective in various applications.

In contrast, other types of flow meters, such as magnetic and electromagnetic flow meters, while non-invasive as well, rely on the electromagnetic principle and typically require that the fluid being measured is conductive. Mechanical flow meters involve moving parts that come into contact with the fluid, thus qualifying them as invasive.