TANKJKT

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  TANKJKT   

Heat Transfer Calculations  for  Jacketed Tanks       

SCREEN SHOTS    Copyright 2015  By chemengsoftware.com    Visit http://www.pipesizingsoftware.com/ for further information and ordering   

 

 

The following page shows the Data Input worksheet. Pop‐up comment boxes and  dynamic prompts guide your data entry.   

 

Heat Transfer in Jacketed Vessels Version 3 by Stephen M. Hall, PE Copyright 2015

All cells are locked except user-defined data; unlock sheet from Tools menu (no password required) VIEW-COMMENTS to see some additional explanations. Scroll down and to the right to enter data.

Project Data Prepared by

xx

Date

xx

Customary US

SI

xx

W.O.

xx

Unit

xx

Area

xx

Equip No

xx

then click the "Restore Saved Calculation" button

Enter value to convert:

Calculate

Vessel Data Calc Title or Description

Temperature Conversion

To restore a saved calculation, select it from the drop-down box below, Client

550 °F

=

287.8 °C

270 °C

=

518.0 °F

Jacket Fluid Data

Vessel Fluid Data

Garvin Example from Table 2

Orientation

vertical vol to tangent

Total working volume

liters

1,497

Inside diameter

mm

1,200.0

Tangent-to-tangent

mm

1,200.0

Heads

Fluid name

Name

Water

1,497 Temperature at jacket inlet

°C

95.0

Bulk Temp

°C

22.0

Use properties of water

Properties from data table:

Material of construction Thickness

Thermal Conductivity

W/m-°C

Specific Heat

Joules/kg-°C

0.121

Density

g/cm³

Viscosity

Pa-s

mm

7.000

mm

0.00000

Internal surface roughness

mm

0.00130

Outside surface roughness

mm

0.00130

Prandtl Number

dimensionless

Internal fouling factor

m²-°C/W

0.00020

Vapor Pressure

kPa abs

Outside fouling factor (jacket)

m²-°C/W

0.00020

Lining Thickness

Thermal Conductivity

W/m-°C

Specific Heat

Joules/kg-°C

Density

g/cm³

Viscosity @20C

Pa-s

Conventional

Half-Pipe Coil

Dimple

0.997 0.00099

45.9

at inlet

2.64

at wall

0.30

Note: k, Cp and density assumed constant at all temperatures

at outlet

1.05

Viscosity is adjusted, but better to enter 3 values below and check box

Flow Rate in Side-Wall Jacket

No Jacket

0.607 4,183.9

N/A

Tank is Baffled

Inlet/Outlet Nozzle Size

0.867 0.00320

Latent Heat of Vap

Side-Wall Jacket

1,737.5

Agitator Data

Enter a value for each heat transfer surface. When one parameter is entered (flow,

Impeller Type

velocity, or pressure drop) the other two are calculated. Red value shows user entry. Total Flow

DN

Impeller Diameter

mm

384.0

Sidewall Jacket

336.7 liters/min

3.0 m/s

8.8 kPa

Blade Height

mm

72.0

112.2 liters/min

2.0 m/s

2.3 kPa

Blade Pitch (90 deg = upright)

degrees

0.0

0.0

Number of blades

Number of Zones

2

Bottom Jacket

Portion of side-wall covered by jacket

1

Internal Coil

0.0

Velocity

Aiding flow (upflow during cooling/downflow during heating)

Pressure Drop

Agitator Rotational Speed

Page 1

90 6

rpm

180

g

( p

g

g/

g

g)

Calculated tip speed

meters/min

217.1

Half-Pipe Coil Jacket Data

Quick Results Nominal Pipe Diameter

DN

Heat Transfer Coefficients

Cross section angle (180 or 120 deg) Spacing between Coils

mm

Process Side

HTF Side

Overall U

120.0

From Vessel to Sidewall Jacket

4,496

1,293

543 W/m²-°C

25.0

From Vessel to Bottom Jacket

3,469

904

446 W/m²-°C

From Vessel to Coil Conventional Jacket Data

Fluid Flow

Not Applicable Annular space dimension

mm

Standard

40.0

Baffled

Agit. Nozzles

Number of agitation nozzles per zone Throat diameter for each nozzle

Flow Rate

Velocity

Pressure Drop

Sidewall Jacket (each zone)

168.3 liters/min

3.0 m/s

8.8 kPa

Sidewall Jacket (combined)

336.7 liters/min

3.0 m/s

8.8 kPa

Bottom Jacket (in parallel with sidewall)

112.2 liters/min

2.0 m/s

2.3 kPa

Internal Coil

2

mm

5.000 60.0

Temperature Effects

Inlet

Outlet

Heat Transferred

Sidewall Jacket

95.0

78.6 °C

137,909 W

Bottom Jacket

95.0

81.1 °C

39,106 W

Internal Coil Dimple Jacket Data

Top Head

Not Applicable Annular space dimension

Agitator

mm

-164 W Estimated power

20.0

Number of passes

1

0.4 kW

x percent transferred as heat

mm

100.0

Transverse

mm

100.0

mm

75.0

Triangular

W

Vessel contents will heat at the rate of 1.70°C per minute

Longitudinal

Dimple pitch

147 W

22.0

Center-to-center distance between adjacent dimples

Mean dimple diameter

35%

Vessel Contents

Square

Environmental Conditions

Viscosity for Fluid inside the Vessel

Air temperature

°C

-5.0

Wind speed

m/s

2.0

Viscosity data at three temperatures Temp.

Bottom Head Jacket

Tank insulation

No Jacket

Conventional

Half-Pipe Coil

Dimple

°F

Type

Covering (on insulated surfaces)

Same type as Side-Wall Jacket

Use this data

Visc.

Temp

cP

°K

68

0.578

293

104

0.446

313

140

0.347

333

Viscosity coefficients

#REF!

(if uninsulated, enter "0" thickness) Series Flow 0

Thickness

Sidewall

mm

25.0

Bottom head

mm

25.0

Top head

mm

0.0

Internal Coil

Temperature of interest Predicted viscosity

A

B

C

-16.56

19,462.31

922.21

77 °F 0.54 cP 298.15 °K

Use this section when you have experimental pressure drop data

No Coil

Hairpin

Helical

Baffle or Harp Coil

Input the known conditions Flowrate liter/min Sidewall

78.7 4

Viscosity mPa-s

Density g/cm³

Press Drop Use Experimental kPa Pressure Drop Data

39.6

1

62.4

19.6

22.5

1

62.4

6.5

Sidewall

(one zone) Bottom Head

Bottom Head

2 See the instruction manual for further information about the use of this pressure drop technique

Page 2

0.97

  Two pre‐formatted reports are included. The first summarizes the input data, and  presents the calculation results. The second includes a timeline, calculated using  60 “time slices” at a user‐defined interval.  Because this is a spreadsheet, it’s easy to customize the reports. Add your logo  and address.  The report formats complement chemengsoftware’s other products such as  PIPESIZE, VentManifold, and others.   

 

JACKETED VESSEL HEAT TRANSFER CLIENT xx REV PREPARED BY xx xx 0 1 2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

DATE

Orientation Total working volume Inside diameter Tangent-to-tangent Heads Material of construction Thickness Lining Thickness Internal surface roughness Outside surface roughness Internal fouling factor Outside fouling factor (jacket) Vessel is baffled

APPROVAL

W.O.

xx UNIT AREA xx xx Garvin Example from Table 2

EQUIP. NO xx REQUISITION NO.

SPECIFICATION NO.

PROCURED BY

INSTALLED BY

Vessel Data vertical, cylindrical Contents 1,497 liters Bulk Temperature 1,200 mm Thermal Conductivity 1,200 mm Specific Heat ASME Torispherical Dished Density 316 SS Viscosity @20C 7 mm Glass mm Agitator Type 0.0013 mm 0.0013 mm Impeller Diameter 0.0002 m²-°C/W Speed 0.0002 m²-°C/W

PAGE

Water 22 0.607 4,184 0.997 0.00099

°C W/m-°C Joules/kg-°C g/cm³ Pa-s

Turbine (Rushton) 384 mm 180 rpm

Jacket Fluid Method for determining flow rate in jacket or coil: Fluid Name Syltherm 800 95 °C Target Velocity Temperature at jacket in Value 3 m/s Thermal Conductivity 0.122 W/m-°C Pressure drop in sidewall determines flow in bottom jacket Specific Heat 1,725.8 Joules/kg-°C Syltherm 800 Density 0.874 g/cm³ Dow Chemical Co. Viscosity 0.00350 Pa-s Polydimethyl-siloxane Estimated vessel wall temp. 29.745 °C Prandtl Number 46 dimensionless Approx. max. vapor pressure 2.6396 kPa abs Jacket and Coil Data Sidewall Jacket Type Half-Pipe Coil Pipe size: 3 DN; 120 deg included angle; 25 mm between loops 11 loops divided into 2 zones; 4 m2 total heat transfer area Bottom Jacket Type Half-Pipe Coil Pipe size: 3 DN; 120 deg included angle; 25 mm between loops 1 m2 heat transfer area; piped in parallel with sidewall Internal Coil Type No Coil Environmental: -5°C, 2 m/s; Sidewall, Bottom, Calcium Silicate insulation Calculated Results Heat Transfer Coefficients Process Side Wall From Vessel to Sidewall Jacket 4,496 1,181 From Vessel to Bottom Jacket 3,469 1,182 From Vessel to Coil

HTF Side 1,293 904

Fluid Flow Flow Rate Velocity Sidewall Jacket (each zone) 168.3 liters/min 3.0 Sidewall Jacket (combined) 336.7 liters/min 3.0 Bottom Jacket (in parallel with sidewall) 112.2 liters/min 2.0 Internal Coil Temperature Effects Inlet Outlet Surface Sidewall Jacket 95.0 78.6 °C 13.0 °C Bottom Jacket 95.0 81.1 °C 13.0 °C Internal Coil 95.0 95.0 95.0 95.0 95.0 Top Hea 8.5 °C 0 kW x 35% Agitator Vessel Contents 22.0 °C Vessel contents will heat at the rate of 1.7 degC per minute

Overall U 543 W/m²-°C 446 W/m²-°C

m/s m/s m/s

Pressure Drop 8.8 kPa 8.8 kPa 2.3 kPa

Heat Transferred 137,909 W 39,106 W -164 W 147 W 176,998 W

JACKETED VESSEL HEAT TRANSFER CLIENT xx REV PREPARED BY xx xx 0 1 2

APPROVAL

W.O.

xx UNIT AREA xx xx Garvin Example from Table 2

SPECIFICATION NO.

PROCURED BY

INSTALLED BY

Vessel Data vertical, cylindrical Contents 1,497 liters Bulk Temperature 1,200 mm Thermal Conductivity 1,200 mm Specific Heat ASME Torispherical Dished Density 316 SS Viscosity @20C 7 mm Glass mm Agitator Type 0.0013 mm 0.0013 mm Impeller Diameter 0.0002 m²-°C/W Speed 0.0002 m²-°C/W

Orientation Total working volume Inside diameter Tangent-to-tangent Heads Material of construction Thickness Lining Thickness Internal surface roughness Outside surface roughness Internal fouling factor Outside fouling factor (jacket) Vessel is baffled

PAGE

Water 22 0.607 4,184 0.997 0.00099

°C W/m-°C Joules/kg-°C g/cm³ Pa-s

Turbine (Rushton) 384 mm 180 rpm

Jacket Fluid Fluid Name Syltherm 800 95 °C Temperature at jacket in Thermal Conductivity 0.122 W/m-°C Specific Heat 1,725.8 Joules/kg-°C Pressure drop in sidewall determines flow in bottom jacket Density 0.874 g/cm³ Viscosity 0.00350 Pa-s

Method for determining flow rate in jacket or coil: Target Velocity Value 3 m/s

Estimated vessel wall temp.

29.745 °C

Sidewall Jacket Type

Half-Pipe Coil

Bottom Jacket Type

Half-Pipe Coil

Internal Coil Type

No Coil

Prandtl Number

45.9 dimensionless

Jacket and Coil Data Pipe size: 3 DN; 120 deg included angle; 25 mm between loops 11 loops divided into 2 zones; 4 m2 total heat transfer area Pipe size: 3 DN; 120 deg included angle; 25 mm between loops 1 m2 heat transfer area; piped in parallel with sidewall

Environmental: -5°C, 2 m/s; Sidewall, Bottom, Calcium Silicate insulation Timeline (calculated at 3-minute intervals)

Temperature

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

DATE

EQUIP. NO xx REQUISITION NO.

100 90 80 70 60 50 40 30 20 10 0 0

15

30

45

60

75

90

105

Time (minutes)

120

135

150

165

180

  Calculations are performed in open‐source Visual Basic for Applications (VBA)  macros. The results are collected into an array that is output to a worksheet. This  makes it easy to review the results without any clutter. 

Heat Transfer in Jacketed Vessels Version 3

Result Details

HTF Film Coefficient, ho Process Film Coefficient, hi Overall Coefficient, U Heat Transferred, Q HTF Flow Rate HTF Pressure Drop HTF Velocity HTF Temperature In HTF Temperature Out HTF Temperature Average HTF Temperature Wall Process Temperature Process Temperature Wall Wall Coefficient, hw Agitator Power Environmental film coefficient, he Jacket-to-environment Ue Jacket-to-environment Qe Process-to-environment Ue Process-to-environment Qe Surface Temperature

1 Sidewall 1,293 4,496 543 137,909 17,511 8.76 3.0 95.0 78.6 86.8 59.9 22.0 29.7 1,181.3 419.9 9.176 1.80 -749

13.0

2 Bottom 904 3,469 446 39,106 5,837 2.28 2.0 95.0 81.1 88.0 55.7 22.0 30.4 1,181.6 147.0 2.850 1.26 -156

36.0

3 Coil 0.0000 0.0000 0.0000 0 0.0000 0.0000 0.000 0.0 0.0 0.0 0.0 22.0 22.0 0.00000

4 Top Head 7.95 3.96 -164

22.0 8.5 1,511.8 7.948

3.96 -164 8.5

W/m2-C W/m2-C W/m2-C W kg/h kPa m/s C C C C C C W/m2-C W W/m2-C W/m2-C W W/m2-C W C