Do Ultrasonic Flowmeters Measure Gas And Liquid at Different Frequencies?

Ultrasonic flowmeter is a non-contact flow measurement instrument that measures the flow rate of a fluid by measuring the time or speed of ultrasonic propagation in the fluid. For gases and liquids, the measurement frequency of ultrasonic flow meters varies due to their different physical properties.

For gases, due to their low sound velocity, a lower ultrasonic frequency is required to achieve higher measurement accuracy. Generally speaking, the frequency of ultrasonic flow meters for gases is between 20-100kHz. For liquids, due to their high sound velocity, in order to accurately measure the fluid flow rate, a higher ultrasonic frequency is required. Generally speaking, the frequency of ultrasonic flow meters for liquids is between 1-5MHz.

In addition, the physical properties such as density and viscosity of gases and liquids are also different, which affects the propagation speed and attenuation degree of ultrasound in them. Therefore, when selecting an ultrasonic flow meter, it is necessary to choose the appropriate frequency and probe type based on the physical characteristics of the measured fluid to ensure measurement accuracy and stability.

In summary, the frequency difference between ultrasonic flow meters measuring gases and liquids is mainly due to the different physical properties of gases and liquids. In practical applications, it is necessary to choose a suitable ultrasonic flowmeter according to the specific situation to ensure the accuracy and reliability of the measurement results.

The above information is just a little bit, let's understand it in another way:

Ultrasonic flowmeter is a non-contact flow measurement instrument that uses the propagation speed of ultrasound in a fluid to measure the flow rate of the fluid. Due to the different propagation speeds and densities of sound waves in gases and liquids, the ultrasonic frequencies used when measuring gases and liquids using ultrasonic flow meters are also different.

For gases, due to their low density and slow propagation speed of sound waves, higher ultrasonic frequencies are required. Generally speaking, the ultrasonic frequency used for gas flow measurement is between 10MHz and 100MHz. Within this frequency range, the attenuation of ultrasound in gas is relatively small, allowing for long-distance propagation, thereby improving measurement accuracy and range.

For liquids, due to their high density and fast propagation speed of sound waves, lower ultrasonic frequencies are required. Generally speaking, the ultrasonic frequency used for liquid flow measurement is between 1MHz-10MHz. Within this frequency range, ultrasound has a significant attenuation in liquids, but can achieve more accurate speed and flow measurement.

Due to the different physical properties of gases and liquids, there are also significant differences in the design, manufacturing, and use of ultrasonic flow meters. For example, in gas flow measurement, it is necessary to consider the compressibility of the gas and the influence of environmental factors such as temperature and pressure; In liquid flow measurement, it is necessary to consider the influence of factors such as viscosity, density, and pressure of the liquid.

In summary, ultrasonic flow meters use different ultrasonic frequencies when measuring gases and liquids, which is due to the different propagation speeds and densities of sound waves in gases and liquids. In practical applications, it is necessary to choose the appropriate ultrasonic frequency and flow meter model based on the specific measurement object to ensure the accuracy and reliability of the measurement results.