The ultrasonic flowmeter is designed based on the geometrical principle that the velocity of the ultrasonic wave propagating in the flowing medium is equal to the average flow velocity of the measured medium and the velocity of the acoustic wave itself. It is also measured by the flow rate to reflect the flow rate. Although the ultrasonic flowmeter appeared only in the 1970s, it is very popular because it can be made into a non-contact type and can be connected to the ultrasonic water level gauge for opening flow measurement without disturbing or resisting the fluid. There are promising flow meters.
Ultrasonic Doppler flowmeters fabricated using the Doppler effect have received widespread attention in recent years and are considered to be ideal gauges for non-contact measurement of two-phase flow.
Fluid oscillating flowmeter
The fluid oscillating flowmeter is designed based on the principle that the fluid will oscillate when flowing under specific flow conditions, and the frequency of the oscillation is proportional to the flow velocity. When the flow cross section is constant, the flow rate is proportional to the flow volume of the pilot volume. Therefore, the flow rate can be measured by measuring the oscillation frequency. This flowmeter was developed and developed in the 1970s. Because it combines the advantages of non-rotating components and pulsed digital output, it has a promising future. At present, typical products include vortex flowmeters and spiral vortex flowmeters.
Maintenance of the turbine flowmeter sensor section:
1. Before the sensor is installed, use the mouth to blow or hand the impeller to make it rotate quickly to see if there is any display. Install the sensor when there is display. If there is no display, check the relevant parts and troubleshoot.
2. When using, keep the measured medium clean and free of impurities such as fibers and particles.
3. When the turbine flow sensor starts to use, the sensor should be slowly filled with the medium, and then the outlet valve should be opened (the valve should be installed at the back end of the flowmeter). It is forbidden to be impacted by the high-speed fluid when the sensor is in the mediumless state.
4. The maintenance period of the turbine flow sensor is generally half a year. When cleaning and cleaning, please be careful not to damage the parts in the measuring chamber, especially the impeller. Please be optimistic about the positional relationship between the guide and the impeller during assembly.
5. When the turbine flow sensor is not in use, the internal medium should be cleaned, and after drying, a protective cover is added at both ends of the sensor to prevent dust from entering, and then stored in a dry place.
6. The filter used in the turbine flowmeter should be cleaned regularly. When not in use, the internal medium should be cleaned. As with the sensor, add a dust jacket and store it in a dry place.
In the case of small flow metering, the film surface ratio is the largest, the Roots flowmeter is second, and the turbine flowmeter is the smallest. The initial flow performance of the volumetric flowmeter should be superior to the velocity flowmeter. For industrial and commercial users with large total gas consumption and low heat load for each gas, the volumetric flowmeter, ie, the membrane meter and the Roots flowmeter, should be preferred to meet the flowmeter requirements of a single burner when used alone. It can also meet the measurement requirements of the maximum flow rate when all burners are used at the same time.
Not all industrial and commercial users can solve the measurement problem by selecting a volumetric flowmeter with a larger range. The volumetric ratio of the volumetric flowmeter is limited, and it is impossible to increase without limit. The selection of the flowmeter cannot be solved. This kind of user has a measurement problem. When the user only uses a single device for gas, or when operating at low flow rate, the initial flow rate and minimum flow rate of a single flow meter may not meet the minimum flow rate requirement. A single large flow meter cannot measure low gas consumption, which will result in Large supply and marketing differences.