Paddlewheel Liquid Flow Meter
Flow meters are the instruments, used to measure the mass and the volumetric flow of liquids and gasses through a pipe. Depending on the material of the flow meter, type of fluid flowing and its application in different fields, the flow meters are divided into different categories, namely differential pressure flow meters, positive displacement flow meters, velocity flow meters, mass flow meters and open channel flow meters. Among these flow meters, the paddlewheel liquid flow meter is a type of velocity flow meter.
Types of Velocity flow meters:
The velocity flow meter shows the direct proportion of fluid velocity and is related to the volumetric flow rate. When Reynold’s number of fluid is greater than 10000, the flow meter becomes less sensitive. They can further be categorized into turbine, vortex shedding, ultrasonic, electromagnetic, and paddlewheel liquid flow meter.
Paddlewheel Type Flow Meter: Classifications & Principles
Paddlewheel flow meters are classified into two mechanical groups. First is the tangential-flow paddlewheel flow meter. It has a water wheel structure and second with a windmill structure called axis-flow paddlewheel flow meter. The flow of the fluid is directly proportional to the motion of the paddle wheel. Therefore, revolving the paddle with the help of the flowing liquid enables to measure the rate of the flow from the number of rotations. Impregnated magnets in the revolving axis and on the border of the paddle help derive the pulses as signals and transform the number of rotations in flow-rate.
The paddlewheel flow meters are used in water or liquids of its category and need a straight pipe before and after the sensor. It has three components, the controller/display, paddle wheel sensor and the pipe. The sensor has free rotating wheels with encapsulated magnets, perpendicular to the flow which rotates with the flowing liquid. The magnet generates a voltage signal which is directly proportional to the flow rate of the fluid. The faster the fluid flows, higher the frequency and voltage produced. The motor is fitted into the pipeline and is available in a variety of materials like polypropylene, stainless steel, and PVDF. This flow meter is very sensitive because of which it has to be used in clean liquids to avoid clogging of the paddles. And if fluid other than water is used, then the flow meter should be used after checking its compatibility with the chemical composition of the fluid.
Benefits of Using Paddlewheel Flow Meters:
The paddlewheel liquid flow meter has a very simple structure with superior reproducibility and receptivity, involving easy installation and low maintenance. It has a compact design and can measure a huge quantity of fluid at a very low cost. It has no pressure drop, hence is ideal for gravitational flows.
Applications of the Flow Meter:
Frequent maintenance is required in order to achieve accurate results in regular course. They are used to regulate the chemical metering pump output, to find the perfect measurement of default fluid volumes in dispensing systems, in irrigation process and notifying the users of the fluctuating flow outside a programmed range.