Measurement Principle and Characteristics of Gas Turbine Flowmeter

Gas turbine flowmeter is a commonly used flowmeter product with the advantages of high accuracy, good repeatability, simple structure, small size, light weight, small pressure loss, long life, simple operation and convenient maintenance. Today we mainly introduce the measurement principle and characteristics of gas turbine flowmeter, hoping to help everyone.

Gas turbine flowmeter measurement principle

The fluid flows through the gas turbine flowmeter housing. Since the blades of the impeller have a certain angle with the flow direction, the impact of the fluid makes the blades have a rotational torque. After overcoming the friction torque and fluid resistance, the blades rotate. After the torque is balanced, the speed is stable. Under certain conditions, the speed is proportional to the flow rate. Since the blades are magnetically conductive, they are in the magnetic field of the signal detector (composed of *magnetic steel and coils). The rotating blades cut the magnetic lines of force and periodically change the magnetic flux of the coil, so that the two ends of the coil induce an electrical pulse signal. This signal is amplified and shaped by the amplifier in the gas turbine flowmeter to form a continuous rectangular pulse wave with a certain amplitude, which can be transmitted to the display instrument to show the instantaneous flow or total amount of the fluid. Within a certain flow range, the pulse frequency f is proportional to the instantaneous flow Q of the fluid flowing through the turbine flow sensor. The flow equation is: q=3600*(f/k) where: f——pulse frequency [Hz] k——meter coefficient of the sensor [1/m3], given by the calibration sheet. Q - instantaneous flow rate of fluid (under working conditions) [m3/h] 3600 - conversion factor. The coefficient of each gas turbine flowmeter is filled in the calibration certificate by the manufacturer. The k value is set in the matching display gas turbine flowmeter to display the instantaneous flow rate and cumulative total.

Gas turbine flowmeter features

The pressure loss is small, and the impeller has anti-corrosion function; it adopts advanced ultra-low power single-chip microcomputer technology, and the whole machine has strong functions, low power consumption and excellent performance. Intelligent flow display with non-linear accuracy compensation function. The accuracy of the correction formula is better than ±0.02%. The instrument coefficient can be set online by buttons and can be displayed on the LCD screen. The LCD screen is intuitive and clear, and has strong reliability. EEPROM is used to protect the cumulative flow and instrument coefficient from power failure, and the protection time is greater than 10 years. It adopts a high-performance MCU central processor to complete data acquisition, processing, display output, and display of the cumulative flow and instantaneous flow on the same screen. Convenient human-machine interface is realized, and data transmission is carried out in standard 485 form.