Turbine Flow Meters: Working Principle, Advantages, and New Developments

Ideally, you can only use a turbine flow meter when the fluid is clean and has low viscosity. This type of flow meter offers high-accuracy measurements and has a comparably low drop in pressure. It is a mechanical flow meter which has a rotor and blades used in measuring fluid flowing through pipes and streams. The faster the fluid flow, the quicker the rotor rotates as well. This proportional rotation and movement of liquid get converted into the flow rate.

Working principle of a turbine flow meter

A turbine flow meter uses a simple mechanical principle of operation. The turbine meter has rotors and blades which rotate as the fluid passes through. The impingement of water on the blade produces the turbine movement which is converted into the volumetric flow rate of the liquid. The faster the rotor moves, the faster the liquid flow rate as well.

Advantages of a turbine flow meter

Turbine flow meters have the following benefits:

  • Economical
  • Simple working principle and technology
  • Easy installation and operation
  • Reliable performance
  • Suitable for both liquid and gas

However, turbine flow meters also have some disadvantages which are:

  • You can only use it when the fluid is clean
  • Careful installation to avoid measurement errors
  • When the bearing degrades, it will affect measurement accuracy
  • Liquid viscosity changes will cause measurement errors
  • Needs calibration
  • May encounter problems because of cavitation

To minimise the problems and issues encountered in using a turbine flow meter, process engineers need to take into account the limitations of this device.

Applications for turbine flow meters

Turbine flow meters are often used in process monitoring involving liquids used in petroleum, chemical, and water treatment industries. In petroleum related applications, a turbine flow meter measures custody transfer of hydrocarbons. When used in water treatment, a turbine flow meter is used for controlling distribution systems. Food and beverage manufacturing plants also use turbine flow meters.

New developments in turbine flow meters for better performance

There is no surprise that the known limitations of turbine flow meters inhibit broader applications. Nevertheless, manufacturers are continually looking at developing turbine flow meters with features that will make the device produce more reliable measurements and efficient performance. For example, ball bearings made of ceramic or sapphire last longer than bearings made from other materials. Another engineering development is creating a turbine flow meter with dual rotors which increases the flow range measurement capacity and also improves accuracy. Rotors that move in two directions also reduce the effect of swirling on measuring liquid flow.

Moreover, new sensor designs will likely minimise the effect of pressure drop on the measurement of turbine flow meters. These advanced sensors could potentially enhance accuracy and reduce the device’s susceptibility to particles present in the liquid.

Some of these innovations are still in development and may not yet be widely implemented. Nevertheless, new designs and developments will continue to produce flow meters that perform better under varying conditions. This is excellent news for many industries that rely on flow meters for many process controls using all types of fluid.