1. Fuji ultrasonic flowmeter working principle
A complete set of Fuji ultrasonic flowmeter is composed of ultrasonic generator, ultrasonic receiver, electronic circuit, flow display, accumulation system and other structures. The flow measurement principle of ultrasonic flowmeter is shown in Figure 1.
As can be seen from Figure 1, the main principle of Fuji ultrasonic flowmeter flow measurement is: to measure the flow rate by detecting the influence of fluid flow on the ultrasonic wave, mainly using the time difference method. The ultrasonic wave is first emitted by transducer 1, and is received by transducer 2 on the other side after passing through channel wall 1, fluid, and channel wall 2. At the same time, the transducer also emits the same frequency ultrasonic wave, which is received by the transducer 1 after passing through the channel wall 2, the fluid, and the channel wall 1. However, due to the existence of the flow rate, the two receive different time, there is a certain time difference, through the time difference, you can know the flow rate, so as to the specific flow value.
2. Fuji ultrasonic flowmeter installation and debugging
Fuji ultrasonic flowmeter installation adjustment mainly involves the following contents:
(1) Transducer installation. It is necessary to first locate the specific location of the transducer installation, accurately locate the position suitable for the transducer installation on both sides of the water transfer project channel, and use the laser theodolite for positioning to ensure that the transducer and the center line of the water transfer channel are 45°. After the transducer is installed, the installation parameters, such as sound path length, sound path Angle, and water level gauge elevation, should be determined in combination with the actual situation of the water transfer project.
(2) Host installation. The key to the installation of the ultrasonic flow meter is to ensure that the ultrasonic signal cable and the power line can be accurately connected. Especially when the signal cable is laid, the two ends should be marked to avoid misconnection and mixed connection.
(3) System debugging. First, input the ultrasonic flowmeter to measure the installation parameters; Then, when there is water in the water transfer channel, the flow meter is self-checked to check the actual working condition of each sound path, check once in the static water state, and check again in the dynamic water state to ensure that the measured value of water flow in the static water state is 0, and indirectly check the accuracy of the flow meter. Finally, check the output parameters of the ultrasonic flowmeter, if everything meets the design requirements, it can be used normally.