Ultrasonic Flow Meter: Working Principle & Its Types

By Author: Nicks Thomas
Total Articles: 5
Comment this article

An ultrasonic flow meter is a volumetric flow measurement apparatus used in a variety of liquid and gas applications. This advanced device is deemed a perfect substitute for vortex and electromagnetic flowmeters. Perfect to be used in a wide array of applications such as custody flow and process flow, these flow meters are of three types named - Doppler ultrasonic flow meters, open channel, and transit time flow meters.

In this post, we will throw light on each of these flow meters and understand how they work. So, without further ado, let’s dive right in.

Types of Ultrasonic Flow Meters

1. Doppler Effect

As the name suggests, Doppler Effect ultrasonic flow meters are based on the effect itself. These flow meters work pretty well with both solid parts and air bubbles. The device has a signal source and a receiver. Signal source or emitting transducer generates ultrasound impulses. The impulse is reflected from the bubbles or solid parts moving by. Depending on the velocity of the moving parts, the form of ultrasonic waves changes. The echo ...
... signal gets back to the receiver and the ultrasonic flow meter analyzes the waves to measure the flow.

2. Open channel ultrasonic flowmeters

As the name suggests open channel ultrasonic meters are used for the measurement of flow levels in open channels. Ultrasonic sounds are sent to the flow surface and the sensor is mounted at the top. Pulses reflecting from the surface in the form of echo come back to the transducer in place. An open channel flow meter requires a flume or weir. Flumes can be parshall or plamer bowlus and weirs can be rectangular or v-notch.

3. Transit time flowmeters

Transit time flow meters work on the propagation velocity of sound waves. This flow meter has 2 sensors that transmit and receive signals in tandem. Apparently, in case of zero flow, you wouldn’t spot any transit time delay between these 2 sensors. In stark contrast, when you have some flow in the pipeline, the sensor emitting the signal in the direction of the flow will capture the signal sooner than the former. By knowing the accurate distance between the 2 sensors, you can easily calculate the flow velocity. There can be more than 2 sensors in the device and ultrasonic flow meters can be in-line or clamp-on as well.

Hope you found the post useful. For more information related to ultrasonic flow meters, feel free to get in touch with us.

Nick Thomas is Passionate Business Analyst and Marketer. Works at oil and Gas System international Dubai. Which make the best membrane nitrogen generator for oil and gas business. You can contact Nicks for the same.