Basic Heat Transfer Concepts

©2006 Armstrong International, Inc.

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Basic Heat Transfer ConceptsBasic Heat Transfer Concepts

2““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Basic Heat Transfer ConceptsBasic Heat Transfer ConceptsBasic Heat Transfer ConceptsBasic Heat Transfer Concepts

And Their Relationships to Heating Coil Selection

TTAirAir

TTSteamSteam

TTsteamsteam >>> T >>> TAirAir

3““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Heat TransferHeat TransferHeat TransferHeat Transfer

• Only occurs when there is a temperature difference

• Flows faster when this difference is higher

• Always flows from high to low temperature

• Is greater with greater surface area

• Some materials transfer heat better than others

4““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Heat Flows from High to LowHeat Flows from High to LowHeat Flows from High to LowHeat Flows from High to Low

TTAirAir

TTSteamSteam

TTsteamsteam >>> T >>> TAirAir

5““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Thermal Conductivity of Common Coil Thermal Conductivity of Common Coil MaterialsMaterials

Thermal Conductivity of Common Coil Thermal Conductivity of Common Coil MaterialsMaterials

Material Thermal Conductivity

Copper 2724

Aluminum 1536

Steel 314

Cupro-Nickle 90/10 310

Cupro-Nickle 70/30 200

Stainless Steel 108

6““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

To Get More Heat Transfer From Bare To Get More Heat Transfer From Bare Tubes . . .Tubes . . .

To Get More Heat Transfer From Bare To Get More Heat Transfer From Bare Tubes . . .Tubes . . .

Add Fins to Increase Surface Area

7““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Relative Heat Transfer:Relative Heat Transfer:Identical Coils w/Different Tube MaterialsIdentical Coils w/Different Tube Materials

Relative Heat Transfer:Relative Heat Transfer:Identical Coils w/Different Tube MaterialsIdentical Coils w/Different Tube Materials

Tube Material Relative HT Capacity

Copper 1.00

Aluminum 1.00

Steel 0.98

Stainless Steel 0.95

8““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Relative Heat Transfer:Relative Heat Transfer:Identical Coils w/Material Combinations*Identical Coils w/Material Combinations*

Relative Heat Transfer:Relative Heat Transfer:Identical Coils w/Material Combinations*Identical Coils w/Material Combinations*

Tube Material Fin MaterialRelative HT

Capacity

Steel Copper Keyfin 1.05

Steel Aluminum Keyfin 1.00

Stainless Steel Aluminum Keyfin 0.94

Steel Steel L Fin 0.92

Stainless Steel Stainless Steel L Fin 0.58

*At 800 FPM, 7FPI & 55 psig

9““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Heat Transfer EquationHeat Transfer EquationHeat Transfer EquationHeat Transfer Equation

Q = U x A x LMTD

where

Q = Heat Transfer Rate (BTU/hr)

U = Heat Transfer Coefficient (BTU/hr/ft2/F)

A = Surface Area (ft2)

LMTD = Log Mean Temperature Difference (b/w the Steam and the Air)

10““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

©2002 Armstrong International, Inc.

Assembly ConceptsAssembly ConceptsAssembly ConceptsAssembly Concepts

11““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Bare Tube CoilsBare Tube CoilsBare Tube CoilsBare Tube Coils

Heat Exchange = U x Surface Area x T

Surface Area 1'' Pipe = 1 Sq Ft / Linear Ft

12““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Extended Surface CoilsExtended Surface CoilsExtended Surface CoilsExtended Surface Coils

Fin Area >>>>> Tube Area

Tube is Irrelevant in Heat Transfer

Fin Element

Plate Fin Wound Fin

13““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Coil ConstructionCoil ConstructionCoil ConstructionCoil Construction

1, 2, and 3 Row Coils

Cond. Conn.

Cond. Header

Finned Tube

Steam Header

Steam Conn.

6 Tubes in the Face4 Tubes in the Face

7 FPI

1 Inch4 FPI

14““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Casings and Air BafflesCasings and Air BafflesCasings and Air BafflesCasings and Air Baffles

Coil Casings

Air Baffles

FlangesCasing Depth

Side Baffle

Header Baffle

Mounting Holes

15““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

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Coil Casing TypesCoil Casing TypesCoil Casing TypesCoil Casing Types

Turned-Out Flange

Standard Flange for Duct-Mounted Coils

Turned-In Flange

Used w/ Removable Coils or Where mounting holes are not needed & smooth casing face is wanted

Dimensions & Spacing7/16"

1-1/2” 3/4”

16““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Removable (Drawer) CoilsRemovable (Drawer) CoilsRemovable (Drawer) CoilsRemovable (Drawer) Coils

• Core installed in a casing w/ flanges on 3 sides and a mounting place on the 4th side

• Coil slides into outer casing like a drawer

Bolt Holes

Lifting Lug Mounting Plate

17““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Coil ConfigurationCoil ConfigurationCoil ConfigurationCoil Configuration

Air Inlet

Air Outlet

Steam

Horizontal Air Flow

Horizontal Tubes

Vertical Tubes

Condensate

18““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

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Coil ConfigurationCoil ConfigurationCoil ConfigurationCoil Configuration

Vertical Up Air Flow Horizontal Tubes

Vertical Down Air Flow Horizontal Tubes

Air Inlet Side

Air Outlet Side

Air Outlet Side

Air Inlet Side

19““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Parallel Multiple CoilsParallel Multiple CoilsParallel Multiple CoilsParallel Multiple Coils

20““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Series Multiple CoilsSeries Multiple CoilsSeries Multiple CoilsSeries Multiple CoilsSteam Supply End

Air Flow

Condensate Return End

21““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

4 Coils in Parallel x 3 Coils in Series• 12 Coils Total

• Drain each coil separately

• 12 Traps may discharge to common Header

Multiple Coil InstallationMultiple Coil InstallationMultiple Coil InstallationMultiple Coil Installation

• Common steam supply OK

22““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Heavy Duty ConstructionHeavy Duty ConstructionHeavy Duty ConstructionHeavy Duty Construction

Min. 0.016” Thick Finson 12 Ga. CS 0.109” Thick Tubes

12 Ga. Casing and Baffles

Sch 80 Connections

Sch 40 Headers

250 psig Standard Pressure Rating

23““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Heavy Duty ConstructionHeavy Duty ConstructionHeavy Duty ConstructionHeavy Duty Construction

• Header, Connections & Tubes (wetted parts) Same Material

• No Galvanic Corrosion

• All Joints Welded

• No Leaks

• Thicker Materials

• Fights Corrosion

Model Number SelectionModel Number SelectionModel Number SelectionModel Number Selection

Extended Surface (Fin Tube) Heating Extended Surface (Fin Tube) Heating CoilsCoils

Extended Surface (Fin Tube) Heating Extended Surface (Fin Tube) Heating CoilsCoils

26““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Which Fin Type?Which Fin Type?Which Fin Type?Which Fin Type?

Standard KeyFin

• Tight joint over wide temperature range

• Best for dissimilar tube and fin materials

27““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Which Fin Type?Which Fin Type?Which Fin Type?Which Fin Type?

L-Fin

• L-shaped foot tension wound over knurled tube

• Best for same material tubes & fins

• Large contact area for high heat transfer

• Some corrosion protection for tube

28““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Tube MaterialsTube MaterialsTube MaterialsTube Materials

Carbon Steel Affords both strength & corrosion resistanceStandard 12 Ga A-214 ERW (1” or 1½” OD)

Optional 10 Ga A-214 ERW

10 Ga or 12 Ga A-179 Seamless

Stainless Steel (304L or 316L)When corrosive steam is present or when ideal piping & trapping practices cannot be followed14 Ga (1” OD) & 12 Ga (1½” OD)

29““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Fin MaterialsFin MaterialsFin MaterialsFin Materials

Steel Fins stand up against aggressive cleaning0.024” Thick on 1” OD or 1 1/2” OD Tubes0.036” Thick on 1 ½” OD Tubes

Aluminum Fins provide the best overall value0.020” Thick Keyfin on all Tube Sizes0.030” Thick Keyfin on all Tube Sizes

Stainless Steel Fins fight high external corrosion0.020” Thick Type 304L & 316L on 1” OD Tubes

Copper Fins provide the best heat transfer0.016” Thick on All Tube Sizes

30““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Conns/Headers/CasingConns/Headers/CasingConns/Headers/CasingConns/Headers/Casing

HeadersSame Material As Tubes With Welded Construction

ConnectionsSteel: Sch 80 (screwed) or Sch 40 (flanged)Stainless Steel: Sch 40 (screwed) or Sch 10 (flanged)

Casing12 Ga. Galvanized Steel or 12 Ga Stainless Steel

31““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Coil TypeCoil TypeCoil TypeCoil Type

• Standard (Type S)

• Centifeed (Type C)

• Tendam (Type T)

• Centifeed Tandem (Type P)

Type S coils are available with opposite-end connections only

Type C coils are available with same-end connections only

AIR FLOW

2-Row Standard Coil 2-Row Centifeed Coil

AIR FLOW

Type T coils have opposite-end connections

Type P coils have same-end connections

AIR FLOW

35““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

Armstrong PromiseArmstrong PromiseArmstrong PromiseArmstrong Promise

We provide intelligent system solutions that improve utility performance, lower energy consumption, and reduce environmental

emissions . . . while providing an “enjoyable experience”!

35““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®

®®

““Expect many Expect many enjoyable experiencesenjoyable experiences!”!”David M. ArmstrongDavid M. Armstrong

®