The difference between real flow calibration and air calibration of ultrasonic flow meters

Ultrasonic flow meters are widely used equipment for measuring liquid and gas flow rates, and real flow calibration and air calibration are two commonly used calibration methods. This article will focus on the main differences between these two calibration methods.

Firstly,

the biggest difference between real flow calibration and air calibration lies in the different fluid media. Real flow calibration is performed by measuring the actual fluid flow rate, while air calibration is performed by measuring the gas flow rate. In practical applications, real flow calibration is mainly applied to liquid flow measurement, such as water, oil, etc., while air calibration is more suitable for gas flow measurement and control fields.

Secondly,

the operating methods for real flow calibration and air calibration are also different. Real flow calibration is carried out in a pipeline under normal working conditions. An ultrasonic flowmeter is installed on the pipeline to measure the fluid, and calibration is performed by comparing the flow rate measured by the flowmeter with the actual flow rate. The advantage of real flow calibration is that it accurately reflects the actual usage situation and is more in line with the actual flow situation. Therefore, real flow calibration is generally the preferred calibration method.

In contrast,

the operation method of air calibration is relatively simple. Due to the small gas density, compressibility, and thermal expansion coefficient, the impact on the flow meter is also small. Therefore, air calibration usually only needs to be carried out under the conditions of standard gas. Specifically, actual working conditions can be simulated by adjusting gas pressure and temperature, and then the flow meter can be calibrated. Although the operation of air calibration is relatively simple, it may be limited in practical applications due to its lower measurement accuracy compared to liquids.

In summary,

there are significant differences between real flow calibration and air calibration in fluid media, operating methods, and application scenarios. In practical applications, appropriate calibration methods should be selected based on specific measurement needs and conditions to ensure the measurement accuracy and reliability of the flow meter.