Last Updated on March 9, 2023 by You Ling
Application of Piezoelectric Ceramics in flow meters
What is flow meters?
A flow meter is a device used to measure the volume or rate of fluid or gas passing through a pipeline or system. It works by sensing the flow and converting it into an electrical or mechanical signal that can be measured and displayed. Flow meters are used in a wide range of applications, including industrial processes, water and wastewater management, and scientific research.
How flow meters works?
The ultrasonic flowmeter is designed based on the principle that the speed of ultrasonic waves in the flowing medium is equal to the geometric sum of the average flow velocity of the measured medium and the speed of the sound wave itself. It also reflects the flow rate by measuring the flow rate.
Classification of ultrasonic flowmeters: 1 Doppler ultrasonic flowmeter: Transducer 1 transmits an ultrasonic signal with a frequency of f1. After passing through the suspended particles or bubbles in the liquid in the pipeline, the frequency shifts and is reflected to the frequency of f2. Transducer 2, this is the Doppler approach, and the difference between f2 and f1 is the Doppler frequency difference fd. Let the fluid velocity be v, the ultrasonic sound velocity be c, and the Doppler frequency shift fd is proportional to the fluid velocity v. When the pipeline conditions, transducer installation position, emission frequency, and sound speed are determined, c, f1, and θ are constants, and the fluid flow rate is proportional to the Doppler frequency shift. The fluid flow rate can be obtained by measuring the frequency shift, and then obtain fluid flow. 2 Time difference ultrasonic flowmeter: The time difference ultrasonic flowmeter measures the fluid flow by using the principle that the time difference between the forward and reverse propagation of sound waves in the fluid is proportional to the fluid velocity.
Which piezo elements can bu used for flow meters?
Piezoelectric elements used in flow meters can vary depending on the type of flow meter and its specific requirements. However, some commonly used piezoelectric elements in flow meters include PZT (lead zirconate titanate) and PVDF (polyvinylidene fluoride) materials. PZT is a popular choice due to its high sensitivity, durability, and temperature stability, making it well-suited for applications where accurate and reliable flow measurements are required. PVDF, on the other hand, is a more flexible and lightweight material that is often used in ultrasonic flow meters and other applications where high sensitivity and resolution are needed.
Flow meters are usually constructed of piezoelectric sensors. For example, these transducers are fabricated using a single-layer piezoelectric disk of our hard-doped piezoelectric ceramic material PZT-40, operating at 200kHz.