Turbine flowmeter by measuring the turbine rotating speed to deduce the flow rate, can be highly accurate measurement of small flow, fast response, used in many fields. Selection needs to consider the nature of the fluid, velocity distribution and the cleanliness of the medium.
Turbine flowmeter is a kind of velocity type flowmeter, it is through the measurement of the rotational speed of the turbine (or impeller) placed in the fluid to deduce the flow rate of the fluid, and then get the flow rate of the fluid. On whether the turbine flowmeter can measure the small flow, can be elaborated from the following aspects:
First, the working principle of the turbine flowmeter
The working principle of the turbine flowmeter is based on the relationship between the rotational speed of the turbine and the fluid flow rate is proportional. When the fluid flows through the turbine, it will drive the turbine to rotate, the faster the turbine rotates, indicating that the fluid flow rate is greater. The turbine flowmeter measures the flow rate by measuring the rotational speed of the turbine and converting it into an electrical signal that is proportional to the flow rate.
Second, the turbine flowmeter's ability to measure small flows
High-precision measurement: turbine flowmeter in precision bearings, can achieve high precision measurement of low flow rate. Its smallest calibre (e.g. DN4) can measure the flow rate of liquid in the range of 0.04~0.25m³/h, which indicates that the turbine flowmeter has the ability to measure small flow rates.
Fast response time: turbine flowmeter has a very fast response time, you can quickly capture the changes in flow, which is particularly important for the need for real-time monitoring of small flows.
Third, the application of turbine flowmeter
Turbine flowmeter is widely used in petroleum, chemical, electric power, gas pipeline network, city gas and other fields, and is used for trade settlement. Its high measurement accuracy, repeatability and stability, wide range, rapid response to changes in flow rate, anti-interference capability and other characteristics, making it one of the commonly used flowmeter in these areas.
Fourth, the use of precautions
Although the turbine flowmeter can measure small flows, but need to pay attention to the following points:
Fluid properties: turbine flowmeter on the fluid viscosity and density requirements, viscosity and density will affect the speed and flow of the fluid. Therefore, in the selection of the need to ensure that the viscosity and density of the measured fluid is suitable for the selection of the turbine flowmeter.
Fluid velocity distribution: turbine flowmeter on the fluid velocity distribution also has certain requirements, usually requires the fluid velocity gradient is less than a certain range (such as 10% ~ 15%). If the velocity gradient is large, it will lead to a reduction in measurement accuracy.
Medium cleanliness: turbine flowmeter on the cleanliness of the measurement medium requires a high degree. If the fluid contains large particles of hard or polluting substances, it may damage the turbine bearings, resulting in measurement interruption or loss of accuracy. Therefore, when using a turbine flowmeter to measure small flows, you need to ensure the cleanliness of the fluid.
In summary, the turbine flowmeter is a velocity type flowmeter with the ability to measure small flows. However, in practical applications, according to the nature of the measured fluid, velocity distribution and media cleanliness and other factors for comprehensive consideration and selection.
Hangzhou Economic Development Area，Hangzhou 310018，China
