| The first turbine flow meter was invented by Reinhard | | | | have a major advantage in the form of their fewer |
| Woltman way back in 1790. He came up with the idea | | | | blades, which makes them more immune to damage |
| in response to a need of studying loss of water flow | | | | from debris. They are also extremely low cost and do |
| velocity in open canals. Since then, the turbine flow | | | | not require any electric supply to measure the flow |
| meter has seen many innovations in terms of | | | | rate. |
| technology. However, the original design persists more | | | | - WoltmanWoltman meters are the first turbine flow |
| or less and is still the preferred flow meter when it | | | | meters invented and continue to be used widely in |
| comes to measuring the flow of water in large | | | | municipal and industrial water applications for the |
| quantities. It is known as the Woltman flow meter. | | | | measurement of flow rates of large volumes of |
| Later developments in the technology have resulted in | | | | water. These meters deliver highly accurate readings |
| the creation of eight different types of turbine flow | | | | as their axis is aligned in line with the direction of flow. |
| meters. While some of the flowmeters have been | | | | - Single JetSingle Jet flowmeters consist of a set of |
| named after the type of water wheels on which they | | | | blades set directly in the path of a stream or jet of |
| are based, some others are named after the | | | | water within a pipe. The stream or jet is created using |
| technology. Broadly speaking, following are the | | | | an orifice. Such types of meters are mainly used for |
| different types of turbine flow meters currently in use: | | | | billing purposes in residential and commercial water |
| - Pelton WheelBased on the original Pelton wheel that | | | | supply operations. |
| was used to turn turbines using flowing water, the | | | | - Multi-jetBased on the same principle as Single Jet |
| Pelton wheel has buckets attached to the outside of | | | | flowmeters, multi-jet flowmeters direct water from |
| wheel. When water or liquid hits these buckets, the | | | | multiple orifices onto blades to make them rotate |
| wheel starts rotating. The Pelton wheel turbine | | | | around a central axis. Multi-jet water meters are also |
| flowmeter has a similar setup in a more compact | | | | used for residential and commercial water supply billing |
| frame and is used to measure the flow of low | | | | purposes. |
| viscosity liquids that are flowing at slow rates. | | | | - CompoundA Compound flow meter is a cross |
| - Paddle WheelPaddle Wheel flow meters are again | | | | between a regular turbine flowmeter and a positive |
| based on the design of a water wheel. These types | | | | displacement meter. It has both a turbine and a positive |
| of flowmeters have shafts that are placed at right | | | | displacement component. When the flow rate is high, it |
| angles to the flow stream. The shafts are attached to | | | | is measured using the rotation speed of the turbine. |
| a lightweight paddle wheel that rotates as the flow | | | | Low flow rate on the other hand is measured using |
| moves the shafts. The speed of rotation of the paddle | | | | the displacement component. These types of hybrid |
| wheel is proportionate to the flow speed of the liquid. | | | | meters are widely used for measuring water flow |
| Paddle wheel flow meters are more effective for | | | | rates in apartment buildings that have varying flow |
| low-speed flows. | | | | rates during the day and night. |
| - PropellerPropeller flowmeters are based on the | | | | - AxialAxial flowmeters have a turbine or rotor that |
| principle of the propeller turbine, which is used in the | | | | rotates around the axis of flow, hence the name. |
| generation of hydroelectric power. Invented by Forrest | | | | These meters are mainly used for measuring the flow |
| Nagler in 1916, a propeller turbine has between three | | | | of petroleum products, industrial liquids, and gases. |
| and six blades and looks similar to the wooden | | | | Depending on the substance for which they are used, |
| propeller found in boats. The blades are fixed and | | | | axial flow meters have different designs for liquids and |
| rotate around a central axis. Propeller flowmeters | | | | gases. |