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『The principle of rotor flowmeter』Related information(v cone flow meter|rotary gas meter|gallon meter|gear meter|metal tube rotameter|glass tube rotameter|nutating disk meter|transit time ultrasonic flow meter|wedge flow meter|pd meters|hydraulic flow meter|ultrasonic water flow meter|water flow meter|air flow meter|magnetic water flow meter|oxygen flow meter|gas flow meter|argon flow meter|air velocity meter|gasoline flow meter|fuel flow meter|ultrasonic water meter|digital water meter|nitrogen flow meter|solid flow meter|Oxygen tank flow meter|digital water flow meter|diesel fuel flow meter|steam flow meter|02 flow meter|compressed air flow meter|oil flow meter|liquid flow meter)
1. Working principle formula of rotor flow meter
The working principle formula of rotor flow meter is based on the force balance relationship in fluid mechanics. 1. Working principle: When the fluid flows through the conical tube from bottom to top, it is intercepted by the rotor, creating a pressure difference between the upstream and downstream of the rotor. This pressure difference acts on the rotor, creating a force that causes it to move upwards. When this force is greater than the gravity of the spine rotor immersed in the fluid, the rotor rises. As the rotor rises, the annular gap area between the rotor and the cone tube increases, and the pressure difference of the fluid acting on the rotor decreases. When the pressure difference is balanced with the rotors gravity (minus buoyancy), the rotor stops at a certain position of the trapped key. When the flow rate changes, the rotor will reach a new equilibrium at the corresponding position
2. Core formula Balance formula: $V_f (\ rhouf - \ rho) g=A_f \ Delta p $Where: - $V_f $is the volume of the rotor - $\ rhouf $is the density of the rotor material - $\ rho $is the density of the measured fluid - $g $is the gravitational acceleration - $A_f $is the cross-sectional area of the largest part of the rotor - $\ Delta p $is the pressure difference before and after the rotor Flow formula: $q-v=\ frac {C_A A_R} {\ sqrt {1- \ beta ^ 4}} \ sqrt {\ frac {2 \ Delta p} {\ rho} $Where: - $q-v $is the volumetric flow rate - $C_A $is the flow coefficient - $A_R $is the annular gap area between the rotor and the cone tube - $\ beta $is the ratio of the maximum diameter of the rotor to the inner diameter of the cone tube - $\ Delta p $is the pressure difference befor
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2. Can the rotor flowmeter flush the liquid from top to bottom
Rotary flow meters are usually not recommended to be flushed from top to bottom. 1. The working principle limits the operation of the rotor flowmeter based on the principle of balancing gravity and fluid forces. Normal installation is vertical installation with fluid flowing from bottom to top, so that the upward force of the fluid is balanced with the gravity of the rotor, stabilizing the rotor in the corresponding position to indicate the flow rate. If the liquid is flushed from top to bottom, the gravity will be in the same direction as the fluid flow, and the rotor will quickly fall, making it impossible to accurately indicate the flow rate based on the principle of balance. It may also damage the internal structure of the flowmeter due to the impact caused by the falling speed being too fast. 2. The structural design requires that the internal structure be designed according to the fluid flow from bottom to top. For example, the design and layout of internal components such as guide rods and conical tubes are to ensure that the rotor can rise smoothly and suspend stably when the fluid flows from bottom to top. If the fluid flows from top to bottom, it may cause the rotor to shake, jam, and other issues during the descent process, affecting the accuracy of the measurement and even causing the rotor to get stuck in the conical tube, damaging the flowmeter. However, in some special short-term flushing operations that can ensure no damage to the flowmeter, after professional evaluation and guidance, top-down flushing may also be performed, but this is not a normal way of use.