Heat Transfer Equipment1

8/7/2019 Heat Transfer Equipment1

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03/17/11 1

Heat Transfer ModesHeat Transfer Modes

Heat is transferred by three modes. i.e.,Heat is transferred by three modes. i.e.,

1) Radiation Mode1) Radiation Mode

2) Conduction Mode2) Conduction Mode

3) Convection Mode3) Convection Mode



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1)1) Radiation ModeRadiation Mode

Heat is radiated from heating source byHeat is radiated from heating source by

electromagnetic waves.electromagnetic waves.

2) Conduction Mode2) Conduction Mode

Heat is transferred by the vibration of metalHeat is transferred by the vibration of metal

molecules in their vicinitiesmolecules in their vicinities

3) Convection Mode3) Convection Mode

Heat is transferred in liquid molecules due toHeat is transferred in liquid molecules due to

density difference caused by the applicationdensity difference caused by the application

of heat.of heat.



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HEAT EXCHANGERSHEAT EXCHANGERS

USESUSES To cool or heat a fluid (gas or liquid)To cool or heat a fluid (gas or liquid)

i.e., Cooler/Heateri.e., Cooler/Heater

To condense a vaporized material .To condense a vaporized material .

(Condenser)(Condenser)

To evaporate a liquid. ( Evaporator )To evaporate a liquid. ( Evaporator )

To recover waste heat. ( Waste HeatTo recover waste heat. ( Waste Heat

Boiler )Boiler )



What are heatWhat are heat

exchangers for?exchangers for? To get fluid streams to the rightTo get fluid streams to the right

temperature for the next processtemperature for the next process reactions often require feeds at high temp.reactions often require feeds at high temp.

To condense vapoursTo condense vapours To evaporate liquidsTo evaporate liquids

To recover heat to use elsewhereTo recover heat to use elsewhere

To reject low-grade heatTo reject low-grade heat To drive a power cycleTo drive a power cycle



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HEAT EXCHANGESHEAT EXCHANGES (Unfired Equipment(Unfired Equipment))

Heat exchanger is the equipment used toHeat exchanger is the equipment used to

exchange heat between two fluids withexchange heat between two fluids with

different temperatures, through a fixed wall,different temperatures, through a fixed wall,

without mixing them.without mixing them.

Their names are based on the utilization.Their names are based on the utilization.



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Types of Heat TransferTypes of Heat Transfer

EquipmentEquipment

1)1) Unfired Equipment:Unfired Equipment:

Heat transfer occurs by conductionHeat transfer occurs by conduction

and convection mode only. Examples of and convection mode only. Examples of

this are coolers, condensers, and heatthis are coolers, condensers, and heatexchangers.exchangers.

2)2) Fired EquipmentFired Equipment

Heat transfer takes place by Radiation,Heat transfer takes place by Radiation,conduction and convection modes.conduction and convection modes.

Examples of this are steam boilers andExamples of this are steam boilers and

furnaces (heaters).furnaces (heaters).



Main categories of Main categories of

exchangerexchangerHeat exchangers

Recuperator s

Regenerators

Wall separating streamsWall separating streams Direct contact

Most heat exchangers have two streams,Most heat exchangers have two streams, hot hot andand

cold cold , but some have more than two, but some have more than two



Recuperators/regeneratoRecuperators/regenerato

rsrsRecuperativeRecuperative

Has separate flow paths for eachHas separate flow paths for each

fluid which flow simultaneouslyfluid which flow simultaneously

through the exchangerthrough the exchanger

transferring heat between thetransferring heat between the

streamsstreams

RegenerativeRegenerative

Has a single flow path which theHas a single flow path which the

hot and cold fluids alternatelyhot and cold fluids alternately

pass through.pass through.

Rotating wheel



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Shell-and-TubeShell-and-Tube Heat ExchangersHeat Exchangers

Exchanger consists of a bundle of tubes enclosedExchanger consists of a bundle of tubes enclosed

in a Shellin a Shell

Two fluids flow against the opposite sides of a tubeTwo fluids flow against the opposite sides of a tube

wall which separate them.wall which separate them. One fluid inside the tubes and the other outsideOne fluid inside the tubes and the other outside

the tubes.the tubes.

The fluids never come in a contact with eachThe fluids never come in a contact with eachother.other.

Heat is passed from the hot fluid to the cold fluid.Heat is passed from the hot fluid to the cold fluid.



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Shell-and-TubeShell-and-Tube Heat ExchangersHeat Exchangers

Tubes:Tubes: Figure shows theFigure shows the

arrangement of Heatarrangement of Heat

Exchanger Tubes.Exchanger Tubes.

It is desirable to place asIt is desirable to place as

many tubes as possiblemany tubes as possible

in a heat exchanger toin a heat exchanger to

increase the surface areaincrease the surface area

for heat transfer.for heat transfer. Tubes are attached to aTubes are attached to a

tube sheet as shown in thetube sheet as shown in the

figure.figure.

Tubesheet

Tubes



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Tube bundleTube bundle

The tubes and tube sheetsThe tubes and tube sheetstogether are called thetogether are called the tubetubebundlebundle..

The tube bundle is installed as aThe tube bundle is installed as asingle unit.single unit.

The bundle is also removed as aThe bundle is also removed as a

unit for inspection, cleaning andunit for inspection, cleaning andrepair.repair.



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Tube Pitch:Tube Pitch:

It is the shortest center-to-center distance between adjacent tubes.It is the shortest center-to-center distance between adjacent tubes.

TypesTypes1) Triangular Pitch1) Triangular Pitch Tubes are laid out on triangular patternsTubes are laid out on triangular patterns

More tubes can be fixed in the shell, so surface area will beMore tubes can be fixed in the shell, so surface area will bemore.more. Prefer in low pressure systemPrefer in low pressure system

2) Square Pitch2) Square Pitch Tubes are laid out on square patterns.Tubes are laid out on square patterns. Less tubes can be fixed in the shell, so surface area will be less.Less tubes can be fixed in the shell, so surface area will be less. Prefer in high pressure area.Prefer in high pressure area.

..



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Tube Pitch:Tube Pitch:

(a) Square Pitch (b) Triangular Pitch



Shell-side flowShell-side flow



Complete shell-and-tubeComplete shell-and-tube



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BafflesBaffles

It is a sort of plate which induce a turbulenceIt is a sort of plate which induce a turbulence

in the shell fluid and gives the support toin the shell fluid and gives the support to

tubes.tubes.

Baffle PitchBaffle Pitch Center-to-center distance between baffles.Center-to-center distance between baffles.

The baffle space is usually between one toThe baffle space is usually between one to

one-fifth the inside diameter of the shell.one-fifth the inside diameter of the shell.



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Types of BaffleTypes of Baffle

Segmental baffles

ntal Baffle



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Types of BaffleTypes of Baffle

Disk-and-doughnut Baffles

– Doughnut Baffle



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Fixed Tube-Sheet H.Fixed Tube-Sheet H.

ExchangerExchanger

In this heat exchanger , both ends of theIn this heat exchanger , both ends of thetube bundle are rigid and fixed.tube bundle are rigid and fixed.

This allows for very little expansion of theThis allows for very little expansion of thetubes.tubes.

This heat exchanger is only used where theThis heat exchanger is only used where thetemperature difference between the twotemperature difference between the twofluids is very small.fluids is very small.

For higher temperature differences it isFor higher temperature differences it isnecessary to provide for differentialnecessary to provide for differential

thermal expansion between the tubes andthermal expansion between the tubes andthe shell during operationthe shell during operation

This can be accomplished by the use of anThis can be accomplished by the use of anexpansion jointexpansion joint on the shell, is shown inon the shell, is shown in

figure on the next slide.figure on the next slide.



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ExchangerExchanger

PartitionBaffles

Fixed Tube-sheets

Fi d T b Sh t HFi ed T be Sheet H



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ExchangerExchanger

With EWith Expansion Jointxpansion Joint

Fl ti H d H tFloating Head Heat



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Floating Head HeatFloating Head Heat

ExchangerExchanger Exchanger having a tube bundleExchanger having a tube bundle

which is removable from the shell.which is removable from the shell. Consists stationary tube sheet, whichConsists stationary tube sheet, which

is clamped between the singleis clamped between the singlechannel flange and a shell flange.channel flange and a shell flange.

At the opposite end of the bundle theAt the opposite end of the bundle thetubes are expanded into a freelytubes are expanded into a freelyriding floating tube sheet orriding floating tube sheet or floatingfloating headhead..

A floating-head cover is bolted to theA floating-head cover is bolted to thetube sheet, and the entire bundle cantube sheet, and the entire bundle canbe withdrawn from the channel end.be withdrawn from the channel end.

The shell is closed by a shell bonnet.The shell is closed by a shell bonnet.



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ExchangerExchanger

The floating head eliminates the differentialThe floating head eliminates the differentialexpansion problemexpansion problem..

The disadvantage are the simple geometryThe disadvantage are the simple geometry

which reduces the number of tubes hencewhich reduces the number of tubes hence

the heat transfer area.the heat transfer area. Also provides an undesirable flow channelAlso provides an undesirable flow channel

between the bundle and the shell.between the bundle and the shell.

These limitations are removed by theThese limitations are removed by the

provision of provision of ““ split-ringsplit-ring ””



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ExchangerExchanger



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ExchangerExchanger

with Split Ringwith Split Ring



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Split-RingSplit-Ring

Floating

headcover

Tube

sheet

Split

ring



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U-Tube Heat ExchangerU-Tube Heat Exchanger Consists of tubes which are bent in the formConsists of tubes which are bent in the form

of a U and rolled into the tube sheet.of a U and rolled into the tube sheet. The tubes can expand freely.The tubes can expand freely.

Baffles may be installed in the conventionalBaffles may be installed in the conventional

manner.manner.

The smallest diameter U-bend, can beThe smallest diameter U-bend, can beturned without deforming the outsideturned without deforming the outside

diameter of the tube at the bend has adiameter of the tube at the bend has a

diameter of three to four times the outsidediameter of three to four times the outside

diameter of the tubing.diameter of the tubing. This omit some tubes at the center of theThis omit some tubes at the center of the

bundle, depending upon the layout.bundle, depending upon the layout.



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U-Tube Heat ExchangerU-Tube Heat Exchanger

The tube bundle can be removed from the heat-The tube bundle can be removed from the heat-exchanger shell.exchanger shell.

Each tube is free to expand or contract withoutEach tube is free to expand or contract withoutany limitations being placed upon it by the otherany limitations being placed upon it by the othertubes.tubes.

The number of tube holes in a given shell is lessThe number of tube holes in a given shell is less

than that for a fixed-tube-sheet exchangerthan that for a fixed-tube-sheet exchangerbecause of limitations on bending tubes of a verybecause of limitations on bending tubes of a veryshort radius.short radius.

The U-tube design reduces the number of joints.The U-tube design reduces the number of joints.In high-pressure construction this feature isIn high-pressure construction this feature isimportant in reducing both initial andimportant in reducing both initial andmaintenance costs.maintenance costs.



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U-Tube Heat ExchangerU-Tube Heat Exchanger



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Kettle Type ReboilerKettle Type Reboiler Exchangers may be installed either vertically orExchangers may be installed either vertically or

horizontally in the field .horizontally in the field . This design is frequently found as heating units at theThis design is frequently found as heating units at the

base of distillation columns.base of distillation columns.

In this type, liquid is vaporized in the Shell usingIn this type, liquid is vaporized in the Shell using

steam or other hot material passing through thesteam or other hot material passing through thetubes.tubes.

An overflow baffle makes sure the tubes are alwaysAn overflow baffle makes sure the tubes are always

submerged in the liquid.submerged in the liquid.

The vapors, can be returned to the distillationThe vapors, can be returned to the distillationcolumn.column.

Non evaporated liquid returns as bottom product.Non evaporated liquid returns as bottom product.



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Kettle Type ReboilerKettle Type Reboiler

Steam

Condensate Liquid from

the bottom of

the column

Bottom

Product

Vapour

back to the

column



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Tank HeatersTank Heaters

The tank heater are usuallyThe tank heater are usuallyU-tube bundle.U-tube bundle.

This design is often usedThis design is often used

for storage tanks of heavyfor storage tanks of heavyfuel oils and high viscosityfuel oils and high viscosity

oilsoils High temperature reduceHigh temperature reduce

the viscosity of oil andthe viscosity of oil andmakes its pumping easy.makes its pumping easy.

Here heating media isHere heating media is

steam which pass throughsteam which pass through

the tubes.the tubes.

Exchanger Operation andExchanger Operation and



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MaintenanceMaintenance..

The start up / shutdown must be done properly to avoidThe start up / shutdown must be done properly to avoid

equipment damage and possible injury to personnel.equipment damage and possible injury to personnel. The unit must be warmed up and cooled off slowly.The unit must be warmed up and cooled off slowly. A sudden change in temperature causes excessive expansionA sudden change in temperature causes excessive expansion

or contraction of the metal. This can damage the tubes andor contraction of the metal. This can damage the tubes andleaks can be develop.leaks can be develop.

Tubes may loose in the tube sheet. Vibration can cause theTubes may loose in the tube sheet. Vibration can cause theloosening of tubes in the tube sheet.loosening of tubes in the tube sheet.

A large pressure difference between inside and outside of A large pressure difference between inside and outside of the tubes may also collapse the tubes.the tubes may also collapse the tubes.

Both sides should be vented on start up to remove anyBoth sides should be vented on start up to remove any

trapped air.trapped air. The cooled fluid should be introduced first when starting upThe cooled fluid should be introduced first when starting up

a heat exchanger.a heat exchanger.



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MaintenanceMaintenance When shutting down, the hotter fluid should be shut off When shutting down, the hotter fluid should be shut off

first.first. Tubes must be cleaned periodically.Tubes must be cleaned periodically. Pressure tests and leak test can be used to check the tubesPressure tests and leak test can be used to check the tubes

in a bundle.in a bundle. A pressure test consists of filling the exchanger with liquidA pressure test consists of filling the exchanger with liquid

or air to pressure higher than atmosphere pressure.or air to pressure higher than atmosphere pressure.

A loss of pressure after a period of time will indicate a leak A loss of pressure after a period of time will indicate a leak Leaky tubes may be re-rolled if they are leaking at the tubeLeaky tubes may be re-rolled if they are leaking at the tube

sheet.sheet. If only a few tubes are leaking somewhere in the middle of If only a few tubes are leaking somewhere in the middle of

the tube, they may be plugged.the tube, they may be plugged. This may be repeated until the number of tubes pluggedThis may be repeated until the number of tubes plugged

interferes with efficient exchanger operation.interferes with efficient exchanger operation.



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Exchangers Using WaterExchangers Using Water

Water is corrosive to steel,Water is corrosive to steel, Particularly when the tube-wall temperature is highParticularly when the tube-wall temperature is high

and dissolved air is present,and dissolved air is present, Therefore, water is kept on tube side to avoid theTherefore, water is kept on tube side to avoid the

corrosion on both shell and tube .corrosion on both shell and tube .

Also, when water travels slowly through a tube, dirt and slimeAlso, when water travels slowly through a tube, dirt and slimeresulting from microorganic action adhere to the tubesresulting from microorganic action adhere to the tubes Which would be carried away if there were greater turbulence.Which would be carried away if there were greater turbulence. As a standard practice, the use of cooling water at velocities less than 1As a standard practice, the use of cooling water at velocities less than 1

m/s should be avoided.m/s should be avoided. Still another factor of considerable importance is the deposition of Still another factor of considerable importance is the deposition of

mineral scale.mineral scale. When water of average mineral and air content is brought to aWhen water of average mineral and air content is brought to a

temperature in excess of 50 oC,temperature in excess of 50 oC, It is found that tube action becomes excessive, and for this reason anIt is found that tube action becomes excessive, and for this reason an

outlet water temperature above 50 oC should be avoided.outlet water temperature above 50 oC should be avoided.

Exchangers UsingExchangers Using



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Exchangers UsingExchangers UsingSteamsSteams

Steam is used as heating medium.Steam is used as heating medium.

Hot steam condensate is corrosive, and care mustHot steam condensate is corrosive, and care mustbe exercised to prevent condensate frombe exercised to prevent condensate fromaccumulating within an exchanger whereaccumulating within an exchanger wherecontinuous contact with metal will cause damage.continuous contact with metal will cause damage.

So, effective steam trap is must.So, effective steam trap is must.

It is advantageous in heating to connect theIt is advantageous in heating to connect thesteam to the tubes of the heater rather than thesteam to the tubes of the heater rather than theshell.shell.

In this way, since the condensate may beIn this way, since the condensate may becorrosive, the action can be confined to the tubecorrosive, the action can be confined to the tube

side alone.side alone. Where as if the steam is introduced into the shell,Where as if the steam is introduced into the shell,

both may be corroded.both may be corroded.



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Air-Cooled HeatAir-Cooled Heat

ExchangersExchangers In the air-cooled exchanger, ambient air is forced orIn the air-cooled exchanger, ambient air is forced or

induced by a fan to flow across a bank of externallyinduced by a fan to flow across a bank of externallyfinned tubes.finned tubes.

A typical air cooler has :A typical air cooler has :

i) A horizontal section containing finned tubes,i) A horizontal section containing finned tubes,

ii) A steel supporting structure with plenumii) A steel supporting structure with plenumchambers and fan ring axial-flow fan,chambers and fan ring axial-flow fan,

iii) Drive assembly, and miscellaneous accessoriesiii) Drive assembly, and miscellaneous accessories

such as louvers, fan guards, fencing and hailsuch as louvers, fan guards, fencing and hail

screens.screens.



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ExchangerExchanger



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Tube BundleTube Bundle

The tube bundle consists of headers,The tube bundle consists of headers,finned tubes, structural-steel sidefinned tubes, structural-steel side

channels, and supports.channels, and supports.

Tube bundle are generally designed toTube bundle are generally designed to

be rigid and self-contained and theybe rigid and self-contained and theyexpand independently of the supportingexpand independently of the supporting

structure.structure.

The fines on the tubes, increase theThe fines on the tubes, increase the

heat transfer areaheat transfer area Aluminum is the most economical finAluminum is the most economical fin

material. Steel finned tubes operatematerial. Steel finned tubes operate

well at higher temperatures.well at higher temperatures.



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Finned TubeFinned Tube

F i n s



Plate and framePlate and frame

Plates hung vertically andPlates hung vertically and

clamped in a press or frame.clamped in a press or frame.

Gaskets direct the streamsGaskets direct the streams

between alternate plates andbetween alternate plates and

prevent external leakageprevent external leakage

Plates made of stainless steel orPlates made of stainless steel orhigher quality materialhigher quality material

Plates corrugated to give pointsPlates corrugated to give points

of support and increase heatof support and increase heat

transfertransfer



Chevron Washboard

Plate typesPlate types

Corrugations on plate

improve heart transfer

give rigidity

Many points of

contact and atortuous flow path

i fview of



view of view of

plateplate

exchangerexchanger““PlatePlate

exchanger”exchanger”

normally refersnormally refersto a gaskettedto a gasketted

plate- and-plate- and-

frameframe

exchangerexchanger

Flow Arrangement within aFlow Arrangement within a



Flow Arrangement within aFlow Arrangement within aPHEPHE

Alternate plates (often same plate types inverted)

Gaskets

arranged for

each stream to

flow between

alternate plates



Cooling TowersCooling Towers

Large shell with packing at the bottom over whichLarge shell with packing at the bottom over whichwater is sprayedwater is sprayed

Cooling by air flow and evaporationCooling by air flow and evaporation

Air flow driven by forced or natural convectionAir flow driven by forced or natural convection

Need to continuously make up the cooling waterNeed to continuously make up the cooling waterlost by evaporationlost by evaporation



Agitated VesselAgitated Vessel Used for batch heatingUsed for batch heating

or cooling of fluidsor cooling of fluids

An agitator and bafflesAn agitator and baffles

promote mixingpromote mixing

A range of agitators areA range of agitators are

usedused

Often used for batchOften used for batch

chemical reactionchemical reaction

P i t d i it h tP i t d i it h t



Printed circuit heatPrinted circuit heat

exchangerexchanger Plates are etched toPlates are etched to

give flow channelsgive flow channels Stacked to formStacked to form

exchanger blockexchanger block

Block diffusionBlock diffusion

welded under highwelded under high

pressure andpressure and

temperaturetemperature

Bond formed is asBond formed is asstrong as the metalstrong as the metal

itself itself



Printed circuit exchangerPrinted circuit exchanger

Note that “compact” does not

mean small but means large

surface area per unit volume



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FansFans Axial-flow fans are large-volume, low-Axial-flow fans are large-volume, low-

pressure devices.pressure devices. Fan diameters are selected to giveFan diameters are selected to give

velocity pressure of approximately 0.1velocity pressure of approximately 0.1in. of water.in. of water.

Total fan efficiency is about 65 per cent,Total fan efficiency is about 65 per cent,and fan drives usually have a minimumand fan drives usually have a minimumof 95 per cent mechanical efficiency.of 95 per cent mechanical efficiency.

Usually fans are provided with four or sixUsually fans are provided with four or six

blades.blades. Fan diameter is generally equal to orFan diameter is generally equal to or

slightly less than the bundle width.slightly less than the bundle width.



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FansFans At the fan tip speeds required for economical performance, aAt the fan tip speeds required for economical performance, a

large amount of noise is produced. The acceptable noise levellarge amount of noise is produced. The acceptable noise levelat the location of the air cooler should be considered in settingat the location of the air cooler should be considered in settingthe maximum speed.the maximum speed.

The axial-flow fan is inherently a device for moving aThe axial-flow fan is inherently a device for moving aconsistent volume of air, when blade setting and speed of consistent volume of air, when blade setting and speed of rotation are constant.rotation are constant.

Variation in the amount of air flow can be obtained byVariation in the amount of air flow can be obtained byadjusting the blade angle of the fan and the speed of rotation.adjusting the blade angle of the fan and the speed of rotation.

The blade angle can be either (1) permanently fixed, (2) handThe blade angle can be either (1) permanently fixed, (2) handadjustable, or (3) automatically adjusted. Air delivery andadjustable, or (3) automatically adjusted. Air delivery andhorsepower are a direct function of blade pitch angle.horsepower are a direct function of blade pitch angle.

Electric motors are the most common fan drivers.Electric motors are the most common fan drivers.

Ai C l d H tAi C l d H t



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ExchangersExchangers AdvantagesAdvantages Air piping system is not required.Air piping system is not required. There is no limit to the air supply volume.There is no limit to the air supply volume. There is practically no fouling on the outsideThere is practically no fouling on the outside

surfaces of the tubes.surfaces of the tubes.

It is economical and easily maintained.It is economical and easily maintained.

DisadvantagesDisadvantages Minimum cooling level is limited by ambientMinimum cooling level is limited by ambient

temperature.temperature. During warm periods, it is common to waterDuring warm periods, it is common to water

spray on the fin tubes which increases thespray on the fin tubes which increases theFin Fan capacity for heat removal due to theFin Fan capacity for heat removal due to thecooling effect of the evaporating water.cooling effect of the evaporating water.



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Forced Draft Air-CoolerForced Draft Air-Cooler

The forced-draft unit pushes air across theThe forced-draft unit pushes air across thefinned tube surface.finned tube surface.

The fan is located below the tube nest.The fan is located below the tube nest. The forced-draft unit requires less horsepowerThe forced-draft unit requires less horsepower

because it moves air at the lowest availablebecause it moves air at the lowest available

temperature (or highest density).temperature (or highest density). Structural costs are lessStructural costs are less Mechanical life is longer.Mechanical life is longer. The forced-draft design offers betterThe forced-draft design offers better

accessibility to the fan for :on-streamaccessibility to the fan for :on-stream

maintenance and fan-blade adjustment.maintenance and fan-blade adjustment. The design also provides a fan and V-beltThe design also provides a fan and V-beltassembly, which are not exposed to the hot-airassembly, which are not exposed to the hot-airstream that exists from the unit.stream that exists from the unit.



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Induced Draft Air CoolerInduced Draft Air Cooler

Induced-draft units are less likely to recirculate theInduced-draft units are less likely to recirculate thehot exhaust air, since the exit air velocity is severalhot exhaust air, since the exit air velocity is severaltimes that of the forced-draft unit.times that of the forced-draft unit.

Induced-draft design more readily permits theInduced-draft design more readily permits theinstallation of the air-cooled equipment above otherinstallation of the air-cooled equipment above othermechanical equipment such as pipe racks or shell-mechanical equipment such as pipe racks or shell-

and-tube exchangers.and-tube exchangers. In a service where sudden temperature changeIn a service where sudden temperature change

would cause upset and loss of product, the induced-would cause upset and loss of product, the induced-draft unit gives more protection in that only adraft unit gives more protection in that only afraction of the surface (as compared with the forced-fraction of the surface (as compared with the forced-draft unit) is exposed to rainfall or snow.draft unit) is exposed to rainfall or snow.



Forced and Induced Draft AirForced and Induced Draft Air

CoolersCoolers

Induced Draft Forced Draft

motor motor

Heat Transfer Equipment1

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