Magnetic Flow Meters
QTRD91 non-contact radar level meter principle
Ultrasonic Level Meters
My company produced some open channel ultraosnic flow meter and help to installed them for customer.
This flow meters are working in a waste water treatment facotry.
Customer need to measure the water flow on open channel.
This type flow meter is good choice for no-pipe flow.
The sensor will meaure the flow's level surface and calculate the flow rate based on the level and channel shape.