How does a turbine flow meter work?

It first converts the flow rate into the rotational speed of the turbine, and then converts that rotational speed into an electrical signal that is proportional to the flow rate. This type of flow meter is used to measure both the instantaneous flow rate and the total cumulative flow rate; its output signal is in the form of frequency, making it easy to digitize. The fluid flows through the sensor housing; due to the angle between the blades of the impeller and the direction of flow, the force exerted by the fluid on these blades generates a rotational torque. After overcoming the frictional torque and fluid resistance, the blades start to rotate, and once the torques are in balance, the rotation speed stabilizes. Under certain conditions, this speed is proportional to the flow rate. Since the blades are magnetic, they find themselves within the magnetic field of the signal detector (which consists of permanent magnets and coils). As the rotating blades cut through the magnetic field lines, they cause a periodic change in the magnetic flux through the coils, thereby generating electrical pulse signals at the ends of the coils. These signals are amplified and shaped by an amplifier, resulting in continuous rectangular pulse waves of a specific amplitude. These waves can be transmitted over long distances to display instruments, which then show the instantaneous flow rate and cumulative volume of the fluid. Within a certain range of flow rates, the pulse frequency f is proportional to the instantaneous flow rate Q of the fluid passing through the sensor; the flow equation is: Q=3600×f/k

Working principle of turbine flowmeters: They utilize the principle of fluid oscillation to measure flow rate. As fluid passes through the turbine flow transmitter in a pipe, two columns of vortices are generated alternately above and below the triangular vortex generator; these vortices are proportional to the flow velocity. The frequency at which these vortices are generated is related to the average velocity of the fluid flowing past the vortex generator as well as the characteristic width of that generator, and can be expressed by the following formula: f = stv/d tjyibiao.cn Where f represents the frequency of vortex generation, in Hz； v is the average velocity of the fluid flowing through the vortex generator, in m/s ； d is the characteristic width of the vortex generator, in m ； st is the Stroh number, a dimensionless quantity, whose value ranges from 0.14 to 0.27. st is a function of the Reynolds number, st=f(l/re). When the Reynolds number Re is in the range of 102–105, the St value is approximately 0.2; therefore, during measurements, it is necessary to keep the Reynolds number of the fluid within 102–105, with the vortex frequency f = 0.2v/d. It can be seen that by measuring the vortex frequency, the average velocity v of the fluid flowing through the vortex generator can be calculated; subsequently, the flow rate q can be determined using the formula q = va, where a is the cross-sectional area through which the fluid flows past the vortex generator.

On the third floor, it refers to vortex streets, not turbines