Flowmeter Termreport

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    FLOW METER & ITS TYPES

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    INTRODUCTION:

    Measuring the flow of liquids is a critical need in many industrial plants. In

    some operations, the ability to conduct accurate flow measurements is so

    important that it can make the difference between making a profit or taking

    a loss. In other cases, inaccurate flow measurements or failure to take

    measurements can cause serious (or even disastrous) results.

    With most liquid flow measurement instruments, the flow rate is determined

    inferentially by measuring the liquid's velocity or the change in kinetic

    energy. Velocity depends on the pressure differential that is forcing the

    liquid through a pipe or conduit. Because the pipe's cross-sectional area is

    known and remains constant, the average velocity is an indication of the

    flow rate. The basic relationship for determining the liquid's flow rate in

    such cases is:

    Q = V x A

    where

    Q = liquid flow through the pipe

    V = Velocity of the fluid

    A = Cross Sectional area of the pipe

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    Defin i t ion:

    Flow meter is an instrument for measuring the rate of flow of water, gas, or

    fuel, especially through a pipe.

    SELECTING A FLOWMETER:

    Experts claim that over 75 percent of the flow meters installed in industry

    are not performing satisfactorily. And improper selection accounts for 90

    percent of these problems. Obviously, flow meter selection is no job for

    amateurs.

    The most important requirement is knowing exactly what the instrument is

    supposed to do. Here are some questions to consider. Is the measurement

    for process control (where repeatability is the major concern), or for

    accounting or custody transfer (where high accuracy is important)? Is local

    indication or a remote signal required? If a remote output is required, is it to

    be a proportional signal, or a contact closure to start or stop another

    device? Is the liquid viscous, clean, or a slurry? Is it electrically conductive?

    What is its specific gravity or density? What flow rates are involved in the

    application? What are the processes' operating temperatures and

    pressures? Accuracy (see glossary), range, linearity, repeatability, and

    piping requirements must also be considered.

    It is just as important to know what a flow meter cannot do as well as whatit can do before a final selection is made. Each instrument has advantages

    and disadvantages, and the degree of performance satisfaction is directly

    related to how well an instrument's capabilities and shortcomings are

    matched to the application's requirements.

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    WORK ING W ITH FLOWM ETERS:

    Although suppliers are always ready to provide flow meter installation

    service, estimates are that approximately 75 percent of the users install

    their own equipment. But installation mistakes are made. One of the most

    common is not allowing sufficient upstream and downstream straight-run

    piping for the flow meter.

    Every design has a certain amount of tolerance to nonstable velocity

    conditions in the pipe, but all units require proper piping configurations to

    operate efficiently. Proper piping provides a normal flow pattern for thedevice. Without it, accuracy and performance are adversely affected.

    Flowmeters are also installed backwards on occasion (especially true with

    orifice plates). Pressure-sensing lines may be reversed too.

    With electrical components, intrinsic safety is an important consideration in

    hazardous areas. Most flowmeter suppliers offer intrinsically safe designs

    for such uses.

    Cal ibra t ion :

    All flowmeters require an initial calibration. Most of the time, the instrument

    is calibrated by the manufacturer for the specified service conditions.

    However, if qualified personnel are available in the plant, the user can

    perform his own calibrations.

    The need to recalibrate depends to a great extent on how well the meter

    fits the application. Some liquids passing through flowmeters tend to be

    abrasive, erosive, or corrosive. In time, portions of the device will

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    deteriorate sufficiently to affect performance. Some designs are more

    susceptible to damage than others.

    Maintenance:

    A number of factors influence maintenance requirements and the life

    expectancy of flowmeters. The major factor, of course, is matching the right

    instrument to the particular application. Poorly selected devices invariably

    will cause problems at an early date. Flowmeters with no moving parts

    usually will require less attention than units with moving parts. But all

    flowmeters eventually require some kind of maintenance.

    Primary elements in differential pressure flowmeters require extensive

    piping, valves, and fittings when they are connected to their secondary

    elements, so maintenance may be a recurring effort in such installations.

    Impulse lines can plug or corrode and have to be cleaned or replaced. And,

    improper location of the secondary element can result in measurement

    errors. Relocating the element can be expensive.

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    F lu id F low Measurement and Reynolds Numb er :

    Veloci ty of the f lu id and pipe s ize: Fluid velocity depends on the head

    pressure, which is forcing the fluid through the pipe. The greater the head

    pressure, the faster the fluid flow rate (all other factors remaining constant),

    and consequently, the greater the volume of flow. Pipe size also affects the

    flow rate. For example, doubling the diameter of a pipe increases the

    potential flow rate by a factor of four.

    Viscos i ty o f the f lu id : Viscosity negatively affects the flow rate of fluids.Viscosity decreases the flow rate of a fluid near the walls of a pipe.

    Viscosity increases or decreases with changing temperature, but not

    always as might be expected. In liquids, viscosity typically decreases with

    increasing temperature. However, in some fluids viscosity can begin to

    increase above certain temperatures. Generally, the higher a fluid's

    viscosity, the lower the fluid flow rate (with other factors remaining

    constant).

    Densi ty of the f lu id: Density of a fluid affects flow rates such that a more

    dense fluid requires more head pressure to maintain a desired flow rate.

    Also, the fact that gases are compressible, whereas liquids essentially are

    not, often requires that different methods be used for measuring the flow

    rates of liquids, gases, or liquids with gases in them.

    Reynolds number : The most important flow factors mentioned above can

    be correlated together into a dimensionless parameter called the Reynolds

    number, which indicates the relative significance of the viscous effect

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    compared to the inertia effect. The Reynolds number is proportional to

    inertial force divided by viscous force. The Reynolds number is

    proportional to fluid flow means velocity and pipe diameter and inversely

    proportional to fluid viscosity.

    Reynolds number (Re) = * D * v/

    Where D = Internal pipe diameter

    v = Velocity

    = Density

    = Dynamic Viscosity

    At very low velocities of high viscosities, Re is low and the fluid flows in

    smooth layers with the highest velocity at the center of the pipe and lower

    velocities at the pipe wall where the viscous forces restrain it. This type of

    flow is called laminar flow and is represented by Reynolds numbers below

    2,000.

    At higher velocities or low viscosities the flow breaks up into turbulent

    where the majority of flow through the pipe has the same average velocity.

    In the "turbulent" flow the fluid viscosity is less significant and the velocity

    profile takes on a much more uniform shape. Turbulent flow is represented

    by Reynolds numbers above 4,000. Between Reynolds number values of2,000 and 4,000, the flow is said to be in transition.

    So Reynolds (Re) number is a quantity that engineers use to estimate if a

    fluid flow is laminar or turbulent. This is important because increased

    http://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.htmlhttp://www.engineeringtoolbox.com/reynolds-number-d_237.html
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    mixing and shearing occur in turbulent flow that results in increased viscous

    losses, which affects the efficiency of hydraulic machines. A good example

    of laminar and turbulent flow is the rising smoke from a cigarette. The

    smoke initially travels in smooth, straight lines (laminar flow) then starts to"wave" back and forth (transition flow) and finally seems to randomly mix

    (turbulent flow).

    Types o f FLOW METERS:

    Followings are the types of flow meters;

    Orif ice Flow Meter :

    An Orifice flow meter is the most common head type flow measuringdevice. An orifice plate is inserted in the pipeline and the differentialpressure across it is measured.

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    Principle of Operat ion:

    The orifice plate inserted in the pipeline causes an increase in flow velocityand a corresponding decrease in pressure. The flow pattern shows aneffective decrease in cross section beyond the orifice plate, with amaximum velocity and minimum pressure at the venacontracta.

    The flow pattern and the sharp leading edge of the orifice plate (Fig. 1.1)which produces it are of major importance. The sharp edge results in analmost pure line contact between the plate and the effective flow, with thenegligible fluid-to-metal friction drag at the boundary.

    Fig. 1.1 Flow pattern with orifice plate

    Types o f Ori f ice Plates :

    The simplest form of orifice plate consists of a thin metal sheet, having in ita square edged or a sharp edged or round edged circular hole.

    There are three types of orifice plates namely

    1. Concentric2. Eccentric and3. Segmental type.

    Fig. 1.2 shows two different views of the three types of Orifice plates.

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    (a) Concentric (b) Eccentric (c) Segmental

    Fig. 1.3 Sketch of orifices of different types

    The concentric type is used for clean fluids. In metering dirty fluids, slurriesand fluids containing solids, eccentric or segmental type is used in such away that its lower edge coincides with the inside bottom of the pipe. Thisallows the solids to flow through without any obstruction. The orifice plate isinserted into the main pipeline between adjacent flanges, the outsidediameters of the plate being turned to fit within the flange bolts. The flangesare either screwed or welded to the pipes.

    Ventur i Meter :

    Venturi tubes are differential pressure producers, based on Bernoullis

    Theorem. General performance and calculations are similar to those for

    orifice plates. In these devices, there is a continuous contact between the

    fluid flow and the surface of the primary device.

    ( a) Concentric ( b) Eccentric ( c) Segmental

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    Class ic Ventur i Constru ct ion :

    1) Lon g Form Ventur i :

    The classic Herchel Venturi tube is given in Fig. 2.1

    It consists of a cylindrical inlet section equal to the pipe diameter; a

    converging conical section in which the cross sectional area decreases

    causing the velocity to increase with a corresponding increase in the

    velocity head and a decrease in the pressure head ; a cylindrical throat

    section where the velocity is constant so that the decreased pressure head

    can be measured ; and a diverging recovery cone where the velocity

    decreases and almost all of the original pressure head is recovered. The

    unrecovered pressure head is commonly called as head loss.

    Fig. 2.1 Classic Long form Venturi

    The classic venturi is always manufactured with a cast iron body and a

    bronze or stainless steel throat section. At the midpoint of the throat, 6 to 8pressure taps connect the throat to an annular chamber so the throat

    pressure is averaged. The cross sectional area of the chamber is 1.5 times

    the cross sectional area of the taps. Since there is no movement of fluid in

    the annular chamber, the pressure sensed is strictly static pressure.

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    Usually 4 taps from the external surface of the venturi into the annular

    chamber are made. These are offset from the internal pressure taps. It is

    through these taps that throat pressure is measured.

    Limi ta t ions :

    This flow meter is limited to use on clean, non-corrosive liquids and gases,

    because it is impossible to clean out or flush out the pressure taps if they

    clog up with dirt or debris.

    2) Shor t Form Ventur i Tubes:

    In an effort to reduce costs and laying length, manufactures developed a

    second generation, or short-form venturi tubes shown in Fig. 2.2

    Fig. 2.2 Shor t fo rm Ventur i

    There were two major differences in this design. The internal annular

    chamber was replaced by a single pressure tap or in some cases an

    external pressure averaging chamber, and the recovery cone angle was

    increased from 7 degrees to 21 degrees. The short form venturi tubes can

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    be manufactured from cast iron or welded from a variety of materials

    compatible with the application.

    The pressure taps are located one-quarter to one-half pipe diameter

    upstream of the inlet cone and at the middle of the throat section. A

    piezometer ring is sometimes used for differential pressure measurement.

    This consists of several holes in the plane of the tap locations. Each set of

    holes is connected together in an annular ring to give an average pressure.

    Venturis with piezometer connections are unsuitable for use with purge

    systems used for slurries and dirty fluids since the purging fluid tends toshort circuit to the nearest tap holes. Piezometer connections are normally

    used only on very large tubes or where the most accurate average

    pressure is desired to compensate for variations in the hydraulic profile of

    the flowing fluid. Therefore, when it is necessary to meter dirty fluids and

    use piezometer taps, sealed sensors which mount flush with the pipe and

    throat inside wall should be used.

    Single pressure tap venturis can be purged in the normal manner when

    used with dirty fluids. Because the venturi tube has no sudden changes in

    contour, no sharp corners, and no projections, it is often used to measure

    slurries and dirty fluids which tend to build up on or clog of the primary

    devices.

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    Types of Ventur i Tub es:

    Venturis are built in several forms. These include

    1. a standard long-form or classic venturi tube (Fig. 2.1)2. a modified short form where the outlet cone is shortened (Fig.

    2.2)

    3. an eccentric form [Fig. 2.3 ( a )] to handle mixed phases or to

    minimize buildup of heavy materials and

    4. a rectangular form [Fig. 2.3 ( b)] used in duct work.

    (a) Eccentric type

    Fig 2.3

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    (b) Rectangular venturi typeFig. 2.3

    Flow Nozzle

    Flange Type Flow No zzle:

    The Flow nozzle is a smooth, convergent section that discharges the flow

    parallel to the axis of the downstream pipe. The downstream end of a

    nozzle approximates a short tube and has the diameter of the

    venacontracta of an orifice of equal capacity. Thus the diameter ratio for a

    nozzle is smaller or its flow coefficient is larger. Pressure recovery is betterthan that of an orifice. Fig. 3.1 shows a flow nozzle of flange type.

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    Fig. 3.1 Flow nozzle

    Different Designs of Flow Nozzle :

    There are different standard designs differing in details of the approach

    section and the length of the throat. Fig. 3.2 shows two accepted designs of

    flow nozzles.

    Flow nozzles are usually made of gun metals, stainless steel, bronze or

    monel metal. They are frequently chromium plated. Sometimes slettite

    coating is provided to have abrasion resistance.

    The pressure tapings may take the form of annular rings with slots opening

    into the main at each side of the flange of the nozzle or of single holes

    drilled through the flange of the main close to the nozzle flange.

    It is not suitable for metering viscous liquids. It may be installed in an

    existing main without great difficulty.

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    Fig. 3.2 (a) The ASME long-radius

    (b) The Simplex type tg

    Advantages :

    1. Permanent pressure loss lower than that for an orifice plate.

    2. It is suitable for fluids containing solids that settle.

    3. It is widely accepted for high pressure and temperature steam

    flow.

    Disadvantages:

    1. Cost is higher than orifice plate.

    2. It is limited to moderate pipe sizes.

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    The simplest pitot tube consists of a tube with an impact opening of 3.125

    mm to 6.35 mm diameter pointing towards the approaching fluid. This

    measures the stagnation pressure. An ordinary upstream tap can be used

    for measuring the line pressure.

    Fig. 4.2 A common industrial type pitot tube

    A common industrial type of pitot tube consists of a cylindrical probe

    inserted into the air stream, as shown in Fig. 4.2 Fluid flow velocity at theupstream face of the probe is reduced substantially to zero. Velocity head

    is converted to impact pressure, which is sensed through a small hole in

    the upstream face of the probe. A corresponding small hole in the side of

    the probe senses static pressure. A pressure instrument measures the

    differential pressure, which is proportional to the square of the stream

    velocity in the vicinity of the impact pressure sensing hole. The velocity

    equation for the pitot tube is given by

    v = C p 2gh

    where C p is the pitot tube constant.

    Impact pressure port

    Static pressure port

    Air flow

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    Fig. 4.3 shows a typical pitot tube which also shows the taps for sensing

    static pressure.

    Fig. 4.3 Typical pitot tube

    The total pressure developed at the point where the flow is stagnated is

    assumed to occur at the tip of a pitot tube or at a specific point on a bluff

    body immersed in the stream.

    The pitot tube causes practically no pressure loss in the flow stream. It is

    normally installed through a nipple in the side of the pipe. It is frequently

    installed through an isolation valve, so that it can be moved back and forth

    across the stream to establish the profile of flow velocity.

    Certain characteristics of pitot tube flow measurement have limited its

    industrial application. For true measurement of flow, it is essential to

    establish an average value of flow velocity. To obtain this with a pitot tube,

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    it is necessary to move the tube back and forth across the stream to

    establish the velocity at all points and then to take an average.

    For high-velocity flow streams, it is required to provide necessary stiffness

    and strength. A tube inserted in a high-velocity stream has a tendency to

    vibrate and get broken. As a result, pitot tubes are generally used only in

    low-to-medium flow gas applications where high accuracy is not required.

    Variable Ar ea Flow Meters

    Basic Principle:

    In the orifice meter, there is a fixed aperture and flow is indicated by a drop

    in differential pressure. In area meter, there is a variable orifice and the

    pressure drop is relatively constant. Thus, in the area meter, flow is

    indicated as a function of the area of the annular opening through which the

    fluid must pass. This area is generally readout as the position of a float or

    obstruction in the orifice.

    The effective annular area in area meter is nearly proportional to height of

    the float, plummet or piston, in the body and relationship between the

    height of float and flow rate is approximately linear one with linear flow

    curve as well as scale graduations.

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    Types o f Variable Area Flow Meters

    Area meters are of two general types:

    1. Rota meters and

    2. Piston type meter.

    Rota meters . In this meter, a weighted float or plummet contained in an

    upright tapered tube, is lifted to the position of equilibrium between the

    downward force of the plummet and the upward force of the fluid in addition

    to the buoyancy effect of the fluid flowing past the float through the annular

    orifice. The flow rate can be read by observing the position of the float.

    Pis ton Type Meter. In this meter, a piston is accurately fitted inside a

    sleeve and is lifted by fluid pressure until sufficient post area in the sleeve

    is uncovered to permit the passage of the flow. The flow is indicated by the

    position of the piston.

    Fig. 5.1 (a) Rota meter

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    5. Minimum Piping Requirement. An area meter usually can be

    installed without regard to the fittings or lengths of straight pipe

    proceedings or following the meter.

    6. Corrosive or Difficult to handle liquid. These can often be handledsuccessfully in an area meter. They include such materials as oil, tar,

    refrigerants, sulphuric acid, black liquor, beverages, aqua regia and molten

    sulphur. In general, if the nature of the fluid does not permit the use of a

    conventional differential pressure type meter because the fluid is dirty,

    viscous or corrosive, certain area meters have an advantage over other

    types of meters.

    7. Pressure Drop. By placing very light floats in over sized meters, flow

    rates can be handled with a combination of very low pressure loss (often

    2.5 cm of water column or less) and 10 : 1 flow range.

    Other FLOW METERS:

    Thermal Flow Meter w i th External Elem ents and Heater :

    A flow meter using heat transfer principle described above has many

    limitations. The temperature sensors and the heater must protrude into the

    fluid stream. Thus these components (particularly the heater) are easilydamaged by corrosion and erosion. Furthermore, the integrity of the piping

    is sacrificed by the protrusions into the fluid stream, increasing the danger

    of leakage.

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    To overcome these problems, the heater and the upstream and

    downstream temperature sensors can be mounted outside of the piping,

    which is shown in Fig. 6.1

    Fig. 6.1 Thermal flow meter with external elements and heater

    In this type of construction the heat transfer mechanism becomes more

    complicated and the relationship between mass flow and temperature

    difference becomes non-linear and to overcome this non-linear relationship,

    heated tube type is introduced.

    Heated Tub e-Type Mass Flow Meter :

    Fig. 6.2 illustrates the non- linear shift in T in a heated -tube-type flow

    meter, where the asymmetricity of the temperature distribution increases

    with flow.

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    Fig. 6.2 Heated tube-type mass flow meter

    In this type of flow meter, when a fluid flows in a pipe, a thin layer (film)exists between the main body of the fluid and the pipe wall. When heat is

    passing through the pipe wall to the fluid, this layer resists the flow of heat.

    If the heater is sufficiently insulated and if the piping material is a good

    conductor, the heat transfer from the heater to the fluid can be

    expressed as

    Q = h A (T w T f )

    where

    Meter

    ThermocouplesTC-2TC-1

    Heat sink Heat sink

    Tube

    Transformer

    Small

    flow

    TC-1 TC-2

    L/2L/2 0

    Zeroflow

    Temperatur e

    oftube

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    h = film heat transfer coefficient

    A = Area of pipe through which heat is passing

    Tw = Temperature of wall

    Tf = Temperature of fluid.

    The film heat transfer coefficient h can be defined in terms of fluid

    properties and tube dimensions.

    These types of flow meters are best suited for the measurement of

    homogeneous gases and are not recommended for applications where the

    process fluid composition or moisture content is variable. In order for these

    flow meters to be useful in a system, both the thermal conductivity and the

    specific heat of the process fluid must be constant.

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    Ult rason ic f low m eter :

    Schematic view of a flow sensor.

    An ultrasonic flow meter is a type of flow meter that measures the

    velocity of a fluid with ultrasound to calculate volume flow. Using ultrasonic

    transducers, the flow meter can measure the average velocity along the

    path of an emitted beam of ultrasound, by averaging the difference in

    measured transit time between the pulses of ultrasound propagating into

    and against the direction of the flow or by measuring the frequency shift

    from the Doppler effect. Ultrasonic flow meters are affected by the acoustic

    properties of the fluid and can be impacted by temperature, density,

    viscosity and suspended particulates depending on the exact flow meter.

    They vary greatly in purchase price but are often inexpensive to use and

    maintain because they do not use moving parts, unlike mechanical flow

    meters.

    http://en.wikipedia.org/wiki/Flow_meterhttp://en.wikipedia.org/wiki/Fluidhttp://en.wikipedia.org/wiki/Ultrasoundhttp://en.wikipedia.org/wiki/Transducershttp://en.wikipedia.org/wiki/Doppler_effecthttp://en.wikipedia.org/wiki/Moving_partshttp://en.wikipedia.org/wiki/Moving_partshttp://en.wikipedia.org/wiki/Doppler_effecthttp://en.wikipedia.org/wiki/Transducershttp://en.wikipedia.org/wiki/Ultrasoundhttp://en.wikipedia.org/wiki/Fluidhttp://en.wikipedia.org/wiki/Flow_meter
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    Means of operat ion:

    There are three different types of ultrasonic flow meters. Transmission (or

    contra propagating transit-time) flow meters can be distinguished into in-

    line (intrusive, wetted) and clamp-on (non-intrusive) varieties. Ultrasonic

    flow meters that use the Doppler shift are called Reflection or Doppler flow

    meters. The third type is the Open-Channel flow meter.

    Principle :

    Ultrasonic flow meters measure the difference of the transit time of

    ultrasonic pulses propagating in and against flow direction. This timedifference is a measure for the average velocity of the fluid along the path

    of the ultrasonic beam. By using the absolute transit times both the

    averaged fluid velocity and the speed of sound can be calculated. Using

    the two transit times and and the distance between receiving and

    transmitting transducers and the inclination angle one can write the

    equations:

    and

    where is the average velocity of the fluid along the sound path and is

    the speed of sound.

    Magnet ic f low m eters :

    Magnetic flow meters , often called "mag meters or electromags, use

    a magnetic field applied to the metering tube, which results in a potential

    difference proportional to the flow velocity perpendicular to the flux lines.

    http://en.wikipedia.org/wiki/Magnetic_flow_meterhttp://en.wikipedia.org/wiki/Magnetic_flow_meterhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Fluxhttp://en.wikipedia.org/wiki/Fluxhttp://en.wikipedia.org/wiki/Magnetic_fieldhttp://en.wikipedia.org/wiki/Magnetic_flow_meter
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    The potential difference is sensed by electrodes aligned perpendicular to

    the flow and the applied magnetic field. The physical principle at work

    is Faraday's law of electromagnetic induction. The magnetic flow meter

    requires a conducting fluid and a non conducting pipe liner. The electrodesmust not corrode in contact with the process fluid; some magnetic flow

    meters have auxiliary transducers installed to clean the electrodes in place.

    The applied magnetic field is pulsed, which allows the flow meter to cancel

    out the effect of stray voltage in the piping system.

    http://en.wikipedia.org/wiki/Faraday%27s_law_of_inductionhttp://en.wikipedia.org/wiki/Electromagnetic_inductionhttp://en.wikipedia.org/wiki/Electromagnetic_inductionhttp://en.wikipedia.org/wiki/Faraday%27s_law_of_induction
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    References:

    B o o k s :

    Lynnworth, L.C.: Ultrasonic Measurements for Process Control

    [Ultrasonic Acoustic Sensing] Brown University

    Web Links :

    www.idconline.com/technical_references/pdfs/instrumentation/Industrial_Instrumentation%20-%20Flow.pdf types of flow meters pdf

    http://www.maxiflo.co.kr/English/Technology/flowmetertypes.htm

    http://www.omega.com/techref/flowcontrol.html

    http://www.maxiflo.co.kr/English/Technology/flowmetertypes.htmhttp://www.omega.com/techref/flowcontrol.htmlhttp://www.omega.com/techref/flowcontrol.htmlhttp://www.maxiflo.co.kr/English/Technology/flowmetertypes.htm
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    Term Report on:

    FLOW METER & Its Types

    Submitted to:

    Sir Mujtaba , Sir Tafzeel

    Submitted by:

    Ghulam Murtaza Roll No # 101

    Muhammad Waleed Hussain Roll No # 102Muhammad Junaid Jamil Roll No # 103

    Muhammad Ammar Mohsin Roll No # 104

    Muhammad Usama Iqbal Roll No # 105

    Hafiz Muhammad Zia Roll No # 106

    Class: BSc Chemical Engineering 2 nd year

    Section: B

    Session: 2012-16

    Date: Tuesday, 10 th December; 2013

    NFC Institute of Engineering & Technology, Multan