What are ultrasonic flow meters?
Ultrasonic flow meters are instruments that measure the flow rate of liquids or gases using high-frequency sound waves. They are increasingly being adopted for applications requiring high-precision measurements.
Which are the measurement principles of ultrasonic flow meters?
The flow meter may rely on two physical principles: the transit-time method and the Doppler effect. WIKA offers solution based on transit-time method where two ultrasonic transducers are positioned on a pipe and alternately send and receive sound pulses both in the direction of the flow and against it. Because the fluid is moving, the pulse traveling in the direction of the flow arrives faster than the one traveling against it. The difference in transit times is directly proportional to the velocity of the fluid, and from this, the volume flow rate can be calculated.
Why choose ultrasonic flow meters over other technologies?
Ultrasonic flow meters are becoming a compelling alternative to traditional volumetric and differential pressure-based instruments and are increasingly considered even in applications involving conductive liquids, where electromagnetic meters have long been dominant. In gas measurements like biogas, these solutions stand out for their resilience. Unlike thermal mass flow meters, which often suffer from reduced accuracy and reliability due to moisture and impurities, ultrasonic technology remains stable and dependable, maintaining measurement integrity even in the presence of such disturbances.
Which are the main types of transit-time ultrasonic flow meters?
Transit-time ultrasonic flow meters are available in different configurations depending on installation requirements and measurement goals. The two most common types are in-line, where the meter has a body matching the pipe characteristics and it is installed along the pipeline, and clamp on, whose transducers are mounted externally on an existing pipe. A third option is the insertion type, where transducers are placed inside the pipe through dedicated fittings.
What is the difference between in-line and clamp on ultrasonic flow meters?
The main difference between in-line and clamp on transit-time ultrasonic flow meters lies in their installation method and the resulting impact on performance and flexibility. In-line ultrasonic flow meters offer the highest level of accuracy, making them ideal for applications where precision is critical. Clamp on ultrasonic flow meters are non-invasive and can be installed on existing pipes without any modification to the system.
Which are the typical applications of in-line ultrasonic flow meters?
In-line ultrasonic flow meters are widely used for gas flow measurement in both fiscal and non-fiscal applications. They are particularly suited for custody transfer, industrial gas distribution, and process control in sectors like oil and gas, petrochemicals, and power generation. They are ideal for demanding environments, including offshore installations and systems with varying gas compositions such as flare gas or biogas. The integration of pressure and temperature sensors allows for advanced calculations like PTZ compensation and molecular weight determination, for applications requiring volume and mass flow conversion. Their ability to operate without pressure loss and without moving parts also makes them a low-maintenance solution for continuous monitoring and diagnostics.
Which are the typical applications of clamp on ultrasonic flow meters?
Mounted externally on the pipe, the clamp on ultrasonic flow meters are installed without interrupting the process or modifying the piping system, making them suitable for temporary measurements, system diagnostics, and flow verification in existing setups. Commonly used in water management and process industries, they are valuable for aggressive or high-purity fluids.
