flow meter types and their principles pdf

Orifice meter Venturi meter Rota meter Pitot tube. There is a large variety of flow measurement device using numerous physical principles.

Electromagnetic Flow Meter Flow Knowledge Keyence America

This meter calculates either mass or volume.

. They provide a simple precise and. This interaction may be that of imparting motion to the. Pitot tubes and fan air inlet cones are also in.

It mea-sures the differential-pressure drop across a constriction in the flows path to infer the flow velocity. The other measures rate of flow Inferential All fluid meters however consist of two distinct parts each of which has different functions to perform. Piston-type flowmeters use an annular orifice formed by a piston and a tapered cone.

An orifice flow meter Figure 1. Cryogenic flow metering techniques 1. Spring and Piston Flow Meters.

There are also ultrasonic flow meters. Mass meters include Coriolis and thermal types. This is also the reason that the next flow meter type was developed.

Flow meters are classed as volumetric or inferential the latter term referring to meters that determine velocity from other variables such as pressure differences across a device such as an orifice plate. An orifice meter is another device to gauge the flow of a liquid through a pipe. It is fitted to the pipe by flanged joint.

Velocity meters consist of turbine vortex shedding electromagnetic and sonic designs. Pitot tubes and fan air inlet cones are also in. Of the system operations.

The most popular type of heating method is electric. Acoustic oscillations are directed through the flow of gases or liquids. It consists of a flat plate containing a circular orifice provided concentrically with the pipe across the flow as shown in Fig.

The piston is held in place at the base of the cone in the no flow position by a calibrated spring. With this indirect method the flow measured is the volume flow rate Q V stated in its simplest terms. Flow measurement is an important process with diverse applications like measuring the flow rate of blood in human beings to measuring and controlling the flow rate in an oil well useful for extraction of oil.

Of the above flow meters will be discussed in the following sections. Depending on the dispersion degree of the received signal the result is determined. V Fluid Velocity.

So the flow rate can be determined by measuring the pressure drop across the restriction. They offer repeatable accurate flow measurements for different applications like semiconductor processing process control etc. Turbine flow meters where frequency velocity 6.

The principle behind these meters is that an ultrasonic signal is transmitted downstream or in the direction of the flow while another signal is transmitted upstream. Cryogenic flow metering techniques 1. The working principle construction calibration etc.

Flow Measuring Device 3. Orifice Plate or Orifice Meter. MPFMs are still classified into categories in terms of technology Chapter 7 and brief descriptions of the most commonly used measurement principles in MPFMs currently available on the market have also been included.

Their simplicity of design and the. Space limitations prevent a detailed discussion of all the liquid flowmeters available today. The most diverse substances are transported and distributed in piping system in every single day they may include solvents chemicals oilgas drinking water fruit juices slurries.

A reliable flow indication is dependent upon the correct measurement of A. In differential pressure meters a restriction is used to create a pressure drop. The mechanical flow meter has a rotational device inside such as a paddle wheel or a propeller.

Inferential type flow meters. Other meters using this basic principle include wedge and target meters. 1827 Types of Flow Meter.

Types of DP Flow Meters This group of flow meter includes orifice plates flow nozzles wedges and venturi tubes all of which are insertion devices that create unrecovered pressure loss as shown in Figure 3. Q V A V 1 Where A Cross-sectional area of the pipe. A flow meter is a device used to facilitate flow measurement.

Because of this the cross-section of the flow is determined by the depth of the pipe or channel and shape that. Cross-correlation flow meter Vortex shedding flow meters flow switches etc. Flow meters can be classified into differential pressure meters variable area meter positive displacement meters magnetic turbine ultrasonic vortex and Coriolis.

23 Venturi Flow meter The venturi flow meter while considered an obstruction flow meter is less of an obstruction than the orifice type. Flow is generally measured inferentially by measuring velocity through a known area. It still does have a certain amount of pressure drop but it is significantly less than the orifice type meter.

That velocity is then used to calculate the volumetric flow. Flow meters can be classified into differential pressure meters variable. Meters and their applications have now been included in the Handbook since wet gas is considered as a subset of multiphase flows.

The liquid flow in the pipe can be equal to the cross-sectional area within a meter the velocity of the liquid flow Q A v. Pressure drop devices based on Bernoulli Principle a Venturi b Orifice plate c Pitot tube 2. Hot wire anemometers based on h fv 4.

Types of Flow Meters. The delta or differential time is used to calculate the velocity of the liquid. Pressure drop devices based on Bernoulli Principle a Venturi b Orifice plate c Pitot tube 2.

The first is the primary element which is in contact with the fluid resulting in some form of interaction. Common types of differential-pressure flow meters are the orifice the pitot tube and the venturi tube. For example an orifice plate may cost only about 50.

The flow of mass can be calculated by. As the name suggests these fluid flow meters used in industries are ideal for measuring liquid flow in open channels. The following points highlight the five main types of devices for measuring of flow in pipes.

These are devices which principle of operation is based on using ultrasonic signal in the measured substance. Scales are based on specific gravities of 084 for oil meters and 10 for water meters. Laser doppler Anemometers etc.

Differential-pressure flow meter This meter operates based on Bernoullis principle. Friction pressure drop packed screens 3. The open channel flow occurs when part of the flowing fluid is open to the free surface.

E Open Channel Meters. Flow Rate Factors for Gases other than Air Gas Factor Gas Factor Gas Factor Acetylene 095 Halocarbon-11 218 Hydrogen Chloride 113 Air 100 Halocarbon-12 205 Hydrogen Sulfide 108 Ammonia 077 Halocarbon-13 190 Isobutane 142. Acoustic flow meters based on Doppler effect 5.

Fall under electrical type flow meters. It forms an important part of several industries like chemical wastewater treatment pulp and paper oil and gas and several others. The measurement of liquid flows in open channels generally involves weirs and flumes.

Point is equal to their sum at another point. The objective of our presentation is comparisons of different flow measuring devices.

Electromagnetic Flow Meters Working Principle Instrumentationtools