TANKJKT Instructions

TANKJKT

Heat Transfer Calculations

for

Jacketed Tanks

USER INSTRUCTIONS

Copyright 2001

by chemengsoftware.com

TANKJKT User Manual Page 2

TABLE OF CONTENTS

INTRODUCTION 3

DATA INPUT 4

PROJECT DATA 5VESSEL DATA 6PHYSICAL DATA ABOUT THE TANK JACKET 7INTERNAL COIL DATA 10DATA ABOUT THE JACKET AND COIL FLUID 11DATA ABOUT THE FLUID INSIDE THE VESSEL 12AGITATOR DATA 13SUMMARY OF THE CALCULATION RESULTS 15

DATASHEET REPORT 16

TIMELINE 17

FLUID DATA 18

DATA TABLES 20

CALCULATIONS 21

SAVING AND RESTORING DATA 22

REFERENCES 23


INTRODUCTIONTANKJKT is an easy-to-use powerful spreadsheet template that calculates the rate of heating or cooling of tanks due to heat transfer from jackets and internal coils.

Vessel heat transfer is complicated. It involves five resistances to heat flow each of which is dependant on specific conditions. Correlations have been developed for many different cases (e.g., half-pipe coil jackets, turbine impellers, etc.). But other cases (dimple jackets, conventional jackets with nozzles) are either poorly researched or are proprietary and not available for use in this, or any, open product.

Our challenge when designing TANKJKT was to keep the data entry as simple and intuitive as possible while maintaining a comprehensive feature set. We think you'll agree that this goal was met.

Data Input is gathered onto a single worksheet, described in detail in these instructions. The results of the calculations are given on a "datasheet" that matches the look of all of chemengsoftware.com's spreadsheet templates.

Fluid Data are included for most common heat transfer fluids. Because the data is regressed against temperature, jacket heat transfer calculations are very fast, accurate, and easily tested with alternative fluids.

The calculations themselves are neatly organized and documented on their own worksheet. If you don't like our correlations you can probably alter this sheet to incorporate your own. That's the flexibility inherent in spreadsheets and the reason why we choose this platform to develop our software!


DATA INPUTAll of your project and calculation case data are entered on the “Data Input” worksheet. The worksheet is designed to simplify your task in assembling the large amount of information needed for a comprehensive calculation. Where your possible input is limited to a specific list of choices (such as materials of construction), TANKJKT presents the choices in the form of check boxes, radio buttons, or pulldown lists. Other data entry fields are checked as you enter data, with unexpected inputs (i.e., those outside “normal” ranges programmed into the spreadsheet) flagged with Warning messages.

Your screen is probably too small to display the entire Data Input form at once. Use the vertical and horizontal scroll bars to reach all of its parts.

You should notice right off the little red triangles that appear in some cells. These indicate that there are “comments” associated with the cell. By hovering your mouse pointer over the cell, the comment box appears, usually with guidance on how to fill in the cell. For example, the comment associated with surface roughness lists values in both Customary US and SI units for several common vessel materials.

Only those cells that receive entry are unlocked (and in red). The others are locked to prevent inadvertent changes. However, if you need to make changes the sheet is easily unlocked by using the Tools… Protection… Unprotect Sheet command (there is no password).

The following pages detail how to complete each section of Data Input.

Project Data

Physical Data about the tank jacket

Internal Coil Data

Data about the jacket and coil fluid

Data about the fluid inside the vessel

Summary of the calculation results

Agitator Information

Vessel Data


1. Project Data

Project data is used in the header section of the datasheet output form. But the data are not involved in any calculations. It is recommended that the text strings be short to ensure they fit within the rather small boxes on the datasheet. Look at the datasheet to see how it fits.

The radio buttons toggle between “Customary US” and “SI” units of measure. When you switch from one to the other all data input data are converted also, so you can freely toggle back-and-forth.


2. Vessel Data

Physical information about the vessel construction is entered here. When running multiple cases on the same vessel, this section will usually remain constant.

The “Calc Title or Description” is used on the Datasheet. You can enter a lengthy description that covers an entire line of the printout. See the Datasheet, just above Line 1, for an example.

TANKJKT always assumes the vessel is oriented vertically and is cylindrical. Changing this value has no effect.

The “Total working volume” is used to calculate the rate of heating or cooling. TANKJKT uses this number to estimate the fill height, and if the jacket covers tank wall that isn’t wetted on the inside then that portion of the jacket is ignored. A warning is displayed if the input for working volume fills the tank higher than the top tangent (where the top head curvature begins), and the volume of the tank to the top tangent (including the bottom head) is displayed for reference.

Inside diameter and tangent-to-tangent dimensions are used for many calculations and are critical input values. They are typically near a 1:1 ratio; very tall tanks (beyond about 3:1 height:diameter) and very squat tanks (1:2) are processed by all of the formulas, but use caution because the underlying heat transfer correlations, especially for the inside heat transfer coefficient, may not be very accurate under those conditions.

Choose the type of head on the tank bottom using the pulldown list. The top head is immaterial to the calculations. The bottom head type is used only for calculating the fill height.

Material of construction for the tank wall is selected from the pulldown list. Wall thickness is important because it impacts the overall heat transfer coefficient. It is assumed that in internal coil is made of the same material as the tank wall.

An inside lining may be selected from the pulldown list, or choose “None” from the list. Linings are typically glass, a polymer such as Teflon, or an exotic metal such as tantalum. Again, enter the thickness of the lining.

Some suggestions are given in the pop-up comment box for typical roughness values. Consider how the tank will be maintained, and the condition of the surface after a period of time. Similarly, fouling factors are entered. You should consider how the condition of the jacket might change over time (e.g., are there corrosion inhibitors in your water?), and cleaning practices for the inside of the vessel. For instance in pharmaceutical, cosmetic or food processing where cleanliness is exceptionally important it is reasonable to set the “internal fouling factor” to zero. If you are uncertain what values to use for roughness or fouling, try running the calculation with alternatives to see the effect on your results; this will help you decide on an appropriate figure.

The check box is used to signify the presence of internal baffles. Propeller and turbine agitators usually work much better with baffles, however if none are present TANKJKT uses appropriate correlations. Since baffles cannot be used with helical ribbon or anchor type impellers, the baffle checkbox is ignored in those cases. And glassed retreat curve impellers are normally accompanied by a “finger” style glassed baffle; the checkbox is ignored for the glassed retreat curve impeller case and it is assumed that there is a baffle.


3. Physical Data about the tank jacket

This part of Data Input has a general section, then additional sections for each of the three types of sidewall jackets. There’s another section for the bottom head.

If you know for certain what type of jacket your tank will have then focus just on the corresponding input section. However, if you intend to compare one type with another, be sure to complete all relevant sections.

Use the radio buttons to select what type of jacket is on the tank. The pulldown list of inlet/outlet nozzle sizes isn’t currently used in any calculation so its value is irrelevant.

Sidewall jackets are often broken into separate “zones” for the purpose of decreasing the temperature change in the jacket fluid or to decrease pressure drop. The TANKJKT calculation procedures don’t differentiate between stacked and interleaved zones, so it doesn’t matter what type your tank uses. Enter the percentage of the sidewall covered by the jacket; it’s usually “1”, but can be any value from .1 to 1.0. For example, if the jacket only covers half the height of the sidewall, enter the value “0.5”.

Half-Pipe Coil Jacket Data

Half-pipe coil jackets are normally constructed of 3-inch pipe; TANKJKT permits 2, 3 or 4-inch. Additional sizes may be added (see the section on Data Tables, page 18).

The cross section angle is either 180 degrees (a true “half-pipe”), or 120 degrees. Enter the appropriate value. This has a big impact on pressure drop, but not so much on the heat transfer coefficient. So when designing a new vessel, you want to compare the effect on temperature change of the jacket fluid (typically much higher with the 120

degree angle).

The last data to enter is the spacing between adjacent coils. This is the actual distance between coils on the surface of the tank, not the distance between centerlines. It is typically in the range of ¾ to 1½ inches (20 to 40 millimeters).

T ank W a ll

120 deg180 deg


Conventional Jacket Data

“Conventional” jackets are found on glass-lined vessels and also often when the primary purpose for the jacket is heating with steam. The jacket consists of an outer shell separated from the vessel wall with an open space (the “annular” space).

TANKJKT recognizes three mutually exclusive cases:

a standard conventional jacket

conventional jacket with internal baffles that direct the jacket fluid around the vessel, similar to a half-pipe jacket

standard conventional jacket with “agitating nozzles” that impart turbulence to the entering fluid.

The “annular space dimension” is the distance between the outside of the vessel wall to the inside of the jacket wall.

If the “Baffled” checkbox is selected, a prompt appears for “baffle spacing.” This is the distance between adjacent baffles.

If the “agitation nozzles” checkbox is selected, prompts appear for entering the number of agitation nozzles and the throat diameter of each nozzle. Input the number of nozzles on the sidewall, ignoring the bottom head. TANKJKT makes a simplifying assumption that if there is a bottom head conventional jacket it will have the same nozzle configuration as the sidewall. By “same” is meant that there are the same number per unit area, rounded up to the next integer. Even if the conventional jacket is continuous around the bottom head and sidewall, as is usually the case, ignore the bottom head for the purpose of this entry.

The throat diameter of the nozzles are assumed to be uniform for all nozzles. Refer to the pop-up comment for typical values.

The remaining checkbox in this section is “Aiding Flow.” Since standard conventional jackets have such a large cross-sectional area, they typically operate in the laminar flow regime, at a velocity around 0.1 ft/sec. When working in cooling service, if the coolant enters the bottom of the jacket and flows upward it will heat along its travel. This causes the fluid to expand slightly, giving it a buoyant force, and increasing its velocity. As a result the heat transfer coefficient from the jacket fluid to the tank wall is increased slightly. The opposite occurs when coolant flows from top to bottom, and heating applications work in reverse.

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Dimple Jacket Data

Dimple jackets are often a good choice, combining low cost with excellent heat transfer. Unfortunately, the correlations published for dimple jackets are less reliable than for half-pipe coils, perhaps only +/-30% accurate. This is true for heat transfer coefficients and also for pressure drop. So, for critical applications always consult with the tank manufacturer.

Enter the requested data. Annular space is the maximum distance between the tank wall and the jacket. Distances between dimples is measured as if a square grid were placed over the jacket wall (i.e., not the actual distance between dimples in the case of triangular pitch). And the mean dimple diameter is a measure of the space occupied by the dimple and surrounding depression. Thus, by manipulating the values for dimple diameter, spacing, and annular space, you affect the calculation for open area available for flow through the jacket.

Bottom Head Jacket

While normal practice is to match the bottom head jacket with the sidewall, TANKJKT supports a different type. Thus, you could specify a conventional jacket on the bottom head coexisting with a half-pipe coil on the sidewall.

Use the radio buttons to select the type of bottom head jacket to model. Whichever type is chosen, the physical parameters are assumed to be the same as those specified for the sidewall jacket of like type.

The only other decision to make is whether the bottom head will be piped in series or parallel.

TANKJKT uses this flow information when it computes the flowrate through the jacket sections. In each case, the flow through the sidewall jacket (if any) is calculated first. Then, the bottom head jacket is calculated.

In series flow, the flowrate through one of the sidewall zones is forced through the bottom jacket. This may result in a ridiculously high pressure drop in some cases, which means that you must make

different design decisions with respect to series/parallel, jacket types, or how the flow is determined (see section on jacket fluid flow).

In parallel flow, the sidewall pressure drop is calculated. Then, the flow through the bottom head jacket that results in the same pressure drop is computed.

If there is no sidewall jacket, the jacket fluid flow parameters (i.e., specific flowrate, velocity, or pressure drop) are used directly on the bottom head jacket. Or, if there is no jacket at all, but just an internal coil, the parameters are used on the coil.

Series Flow Parallel Flow


4. Internal Coil Data

Internal coils are helical when high heat transfer is required, or hairpin when the heat duty is low. Typically, the coil diameter is 1/30 of the vessel inside diameter, and the coils are

spaced so that the distance between them equals their diameter. Using those rules of thumb, and assuming tank baffles that are 1/12 the tank diameter, suggested values for helical coils are displayed next to the Internal Coil Data Input section.

The flowrate through the coil is determined by criteria established in the Jacket Fluid Data section (next page). If there is an external jacket in addition to the coil, then the flow through the jacket is established. The pressure drop through the jacket is calculated. It is assumed that the internal coil is piped in parallel with the external jacket, and the flowrate is that which results in the same pressure drop as the jacket.


5. Data about the jacket and coil fluid

TANKJKT includes a database with physical properties of many heat transfer fluids correlated with temperature. This is a valuable feature because it makes comparison of different fluids at different temperatures so easy and fast. You might even find yourself turning to TANKJKT just to look up physical properties of an included fluid.

All major heat transfer fluids sold in 2001 are in the database. For the glycol-based low temperature fluids such as Therminol FS, properties are given for a range of concentrations.

In addition, non-proprietary chemicals such as water, steam, ammonia, alcohols, etc. are found in the database. See the complete list on the next page.

You can add more compounds to the database. See the Fluid Data section (page 18) for a list of included fluids, and instructions on how to add your own.

On the Data Input screen simply choose a fluid from the pulldown list, then enter the bulk temperature of the fluid supply. Properties are automatically filled in.

The only condensing vapor supported by TANKJKT is steam. Heat transfer fluids such as Dowtherm A that can be used in vapor/liquid service are not supported at this time.

In the second part you provide your instruction on how to compute the fluid flowrate. The choices are:

Specify flowrate per zone. Clicking this activates the prompt "Flowrate" and displays the units (gal/min or liters/min). Enter the desired rate. As described earlier, this rate will be used for the sidewall jacket (one zone) if there is one. If no sidewall jacket it's used for the bottom head jacket. If no jacket, the flow is used for the internal coil.

Target velocity in jacket. If this is checked, TANKJKT calculates the flowrate that equates to the velocity you enter. For half-pipe coil, standard conventional, and baffled conventional jackets the flow area is constant throughout the jacket making this a straightforward calculation. Flow for conventional jackets with agitating nozzles is calculated by using the flow area of the nozzles, so the velocity is taken at the nozzles and should be very high in comparison with other types of jackets. For dimple jackets the velocity is established for the most constricted portions of the jacket, that which is between dimples.

Target pressure drop. It's often desirable to specify the pressure drop through a jacket. Hydraulic balance is achieved when pressure drops are equalized. TANKJKT calculates the flowrate that results in the pressure drop specified.


New in Version 2.03

TANKJKT now provides a method for utilizing experimental pressure drop data. If you have data from your manufacturer, providing pressure drop at a certain flowrate, you can input the data into TANKJKT and instruct that this be used to calculate the pressure drop at different flowrates or with other jacket fluids.

It works by correlating pressure drop with the flowrate squared, the velocity squared, and the density.

Enter your experimental data on the Data Input sheet and Check the appropriate boxes next to the Flow Rate selection criteria.


6. Data about the fluid inside the vessel

Due to the wide variety of fluids heated or cooled in reactors there is no database included with TANKJKT. You must enter the bulk temperature, thermal conductivity, specific heat, density, and viscosity.

TANKJKT does make its own approximation for the viscosity at the vessel wall. The estimated wall temperature is printed on the Datasheet, and the approximated viscosity is shown here on the Data Input section as well as on the Datasheet. The Lewis-Squires extrapolation method is used; we think this is sufficiently accurate for heat transfer purposes.

Lewis-Squires correlation:viscosity^-.2661 = (known visc)^-.2661 + (T - Tknown)/233


7. Agitator Data

The type of impeller, its size, and speed have an important effect on the inside heat transfer coefficient.

TANKJKT lets you choose from the following types of impellers:

Alloy 3-blade retreating. This is similar to a glass-steel retreat-blade impeller, but constructed of stainless steel or some other alloy.

Anchor. Generally used for viscosities from 20,000 to 100,000 cP, anchors are lower cost than helical coils, and often provide better heat transfer.

Glass-steel retreating. This is the workhorse impeller for glass-lined reactors, although this is changing with the introduction of new impeller styles and materials. Heat transfer is worse than with the alloy retreating blade style (above) which is attributed to more slippage around its curved surfaces.

Helical Ribbon. This proximity type of agitator is generally used for higher viscosity fluids (100,000 to 1,000,000 cP, except highly non-Newtonian liquids which tend to rotate with the impeller and are sheared near the vessel wall.

No Agitator. Inside heat transfer coefficients are very low when there is no agitation.

Paddle. Very similar to a turbine, but with only two or four blades. Generally with a diameter greater than 0.6 of the tank diameter, turning at a slow speed.

Propeller. Applicable when the viscosity is less than about 2000 cP, and for vessel volumes less than 1500 gallons (6000 liters) because they weigh much more (e.g., cost more) than turbines.

Pumped Circulation (no agitator). TANKJKT does not model circulation with jets, but instead treats this as if the liquid flows through the vessel as if it were a large pipe.

Retreating-blade Turbine.

Turbine (Rushton). May have flat or pitched blades.


Different prompts appear after selecting the agitator type from the pulldown list. These relate to impeller diameter, height, pitch, and rotational speed. Suggested values appear to the right of the corresponding data input cells; the suggestions are approximately the values that were used when the correlations were developed. If your geometry is much different from the suggestions then the accuracy may be correspondingly worse.

Some vessels use multiple impellers. This is especially true when the tank is very tall (more than 1-1/2 times the diameter). The literature does not provide correlations for multiple impellers; however, researchers report that the heat transfer is not much different when there are two impellers compared to one. Our recommendation is to input the geometry for one impeller, even if there are several, and leave it at that.


8. Summary of the calculation results

Calculations are performed as data is entered (if "Automatic" calculation is turned on, the default

condition). Refer to the "Quick Results" section on the Data Input screen to see the effect of your inputs. This is most often used to test alternatives such as choice of heat transfer fluid, impeller diameter, and flowrate in the jacket.

When you are finished with your "What if" experimentation, click on the "Datasheet" tab at the bottom of the screen where the completed calculation and assumptions are waiting for final review and printing.


DATASHEET REPORTThe datasheet is designed to match the look and feel of chemengsoftware’s other spreadsheet products. Input data and results are neatly arranged ready for printing and issuing to your client or for filing in your calculation file. Since this is a spreadsheet you are free to annotate the datasheet, or change it permanently to your liking.

Various printer brands and types react differently to the datasheet output. While a typical HP LaserJet prints it perfectly, a HP DeskJet (inkjet) printer expands it horizontally causing it to split to a second page. This is annoying but can be rectified if necessary by changing the Page Setup… to “Fit to 1 Page”.

You can save completed datasheets in a new Excel workbook by following this procedure:

1. In addition to TANKJKT, open an existing workbook or create a new one.

2. Complete your calculation in TANKJKT as usual.

3. While viewing the Datasheet worksheet, COPY the worksheet to your alternate workbook.

Check this box!


TIMELINEThe timeline is an exciting feature of TANKJKT. It is a graph that shows the temperature change of the vessel contents of a period of your choosing. The calculations are repeated for each of 60 data points; the viscosity of the vessel contents is adjusted for each calculation using the built-in correlation.1

The printed form is the same as the Datasheet report, except the bottom portion where results are printed are replaced with the graph.

To create a timeline, go to the Timeline worksheet. In the second row, enter a value for “Interval” to indicate how frequently the calculations will be repeated. For example, inputting the number “3” means that the initial rate of cooling will be assumed constant for 3 minutes, then the calculations will be repeated with the new starting temperature. Since 60 intervals are computed, the duration of your timeline will be 60 times the interval, or in this example, 3 hours.

After entering the interval, click on the “New Timeline” button. There will be a short pause as the timeline is recalculated. You are returned to the Data Input worksheet, signifying that the calculations are done. You can now go back to the

Timeline worksheet to view or print it.

1 The Lewis-Squires correlation for estimating viscosity at a new temperature is intended only for use in these heat transfer calculations and should not be construed as an accurate value. It works best with Newtonian fluids over relatively small temperature ranges.

JACKETED VESSEL HEAT TRANSFER

CLIENT EQUIP. NO PAGE

REV PREPARED BY DATE APPROVAL W.O. REQUISITION NO. SPECIFICATION NO.

0 S. Hall Feb-05-97 1 UNIT AREA PROCURED BY INSTALLED BY2 Reaction Bldg 15

2500 Liter Stainless Steel Reactor

1 Vessel Data2 Orientation vertical, cylindrical Contents Water3 Total working volume 900 gallons Initial Temperature 100 °F4 Inside diameter 60 inches Thermal Conductivity 0.36 Btu/h-ft-°F5 Tangent-to-tangent 72 inches Specific Heat 1.00 Btu/lb-°F

6 Heads ASME Torispherical Dished Density 61.81 lb/ft³7 Material of construction 316 SS Viscosity 0.84 cP

8 Thickness 0.3 inches 2.032 lb/ft-h9 Lining Glass Viscosity at wall 1.18 cP

10 Thickness 0 inches 2.855 lb/ft-h

11 Internal surface roughness 0.0001 inches Agitator Type Retreating-blade Turbine12 Outside surface roughness 0.0070 inches Impeller Diameter 20 inches13 Internal fouling factor 0 ft²-hr-°F/Btu Speed 30 rpm

14 Outside fouling factor (jacket) 0.001 ft²-hr-°F/Btu15 Vessel is baffled

16 Jacket Fluid17 Method for determining flow rate in jacket or coil: Fluid Name Water18 Target Pressure Drop Temperature at jacket inlet 40 °F19 Value 10 psi Thermal Conductivity 0.34 Btu/h-ft-°F

20 Specific Heat 1.00 Btu/lb-°F21 Pressure drop in sidewall determines flow in bttm & coil Density 62.70 lb/ft³22 Viscosity 1.40 cP23 3.38 lb/ft-h24 Estimated vessel wall temp. 82 °F Prandtl Number 9.84 dimensionless

2526 Jacket and Coil Data27 Sidewall Jacket Type Half-Pipe Coil Pipe size: 3 inches; 180 deg included angle; 0.10 inches between loops28 8 loops divided into 1 zones; 41 ft² total heat transfer area29 Bottom Jacket Type Half-Pipe Coil Pipe size: 3 inches; 180 deg included angle; 0.10 inches between loops30 19 ft² heat transfer area; piped in parallel with sidewall

31 Internal Coil Type Helical Pipe size: 2 inches inches; 2,000 inches long32 70.2 ft² heat transfer area33

34 Timeline (calculated at 3-minute intervals)3536

3738

394041424344

4546474849505152

XYZ Co. R-110

1502-63

0.00

20.00

40.00

60.00

80.00

100.00

120.00

0 15 30 45 60 75 90 105 120 135 150 165 180

Time (minutes)

Interval 3.0 minutes betw een calculations 180.0 minutes duration

JACKETED VESSEL HEAT TRANSFER

CLIENT EQUIP. NO PAGE

NEW TIMELINE


FLUID DATAThe fluid data is an extremely valuable feature of TANKJKT. Heat transfer fluids from leading companies such as Solutia, Dow, Du Pont, Calflo and others are included. You can easily add more fluids to the table.

Data in the table are in the following units:

Temperature..................degrees C (except viscosity which uses degrees K)

Thermal Conductivity. . .Btu/hr-ft-°F

Specific Heat.................Btu/lb-°F

Density..........................relative to water

Viscosity........................cP

Vapor Pressure..............mm Hg

Data are regressed linearly for thermal conductivity, specific heat, and density:

property = mt + b

Viscosity is fit to a curve of the form (Vogel equation):

ln(cP) = A + B/(t + C)

Vapor Pressure is fit to a curve of the form (Antoine Equation):

log(VP) = A - B/(t + C)

A section of the Fluid Data worksheet is provided for calculating the coefficients in the above correlations. Select units for each of the properties corresponding with your source of data. Enter the properties at seven temperatures and the coefficients are immediately calculated. The input data are graphed along with the values predicted from the new coefficients. When satisfied, click on the “Add Fluid to Database” button to move the new data into the data table. NOTE: if the fluid name duplicates one already in the table then the data is not moved. You must first delete the row in the table containing the old data, or rename the new fluid to a unique name. There is no error checking in this procedure! It is your responsibility to ensure that all input fields are completed and correct.

To increase the accuracy of the viscosity equation, three sets of coefficients are provided for a low, medium, and high temperature range. This complicates the calculation of viscosity, but the hard work is done by the computer!

TIP: When you often utilize the same material inside the vessel, you can keep its temperature-dependant data available for handy reference. Include your process fluid in the fluid data table. Then, when entering the physical properties for the fluid inside the vessel (see page 13), temporarily choose that fluid as your jacket fluid. Enter a temperature for the jacket equal to the inside temperature. The jacket data fields will display the properties that you can manually re-enter for the inside fluid. Be sure to return the jacket fluid and temperature to its normal condition before proceeding.


List of fluids in the database:

AirAmmoniaArgonButane, iso-Butane, n-Calflo AFCalflo FGCalflo HTFCalflo LTCarbon DioxideChemtherm 550Dowfrost HD, 10 vol%Dowfrost HD, 20 vol%Dowfrost HD, 30 vol%Dowfrost HD, 40 vol%Dowfrost HD, 50 vol%Dowfrost HD, 60 vol%Dowfrost HD, 70 vol%Dowfrost, 10 vol%Dowfrost, 20 vol%Dowfrost, 30 vol%Dowfrost, 40 vol%Dowfrost, 50 vol%Dowfrost, 60 vol%Dowfrost, 70 vol%Dowfrost, 80 vol%Dowfrost, 90 vol%Dowtherm 4000, 10 vol%Dowtherm 4000, 20 vol%Dowtherm 4000, 30 vol%Dowtherm 4000, 40 vol%Dowtherm 4000, 50 vol%Dowtherm 4000, 60 vol%Dowtherm 4000, 70 vol%Dowtherm 4000, 80 vol%Dowtherm 4000, 90 vol%Dowtherm A

Dowtherm GDowtherm HTDowtherm JDowtherm MXDowtherm QDowtherm RPDowtherm SR-1, 10 vol%Dowtherm SR-1, 20 vol%Dowtherm SR-1, 30 vol%Dowtherm SR-1, 40 vol%Dowtherm SR-1, 50 vol%Dowtherm SR-1, 60 vol%Dowtherm SR-1, 70 vol%Dowtherm SR-1, 80 vol%Dowtherm SR-1, 90 vol%EthaneEthyleneHitecIlexan SJarytherm AZ320Jarytherm BT06Jarytherm DBTMarlotherm LHMarlotherm NMarlotherm P1Marlotherm P2Marlotherm SHMarlotherm XMethaneMobiltherm 603Multitherm IG-2Multitherm PG-1NitrogenOxygenParatherm HEParatherm NFParatherm OR

PropanePropyleneRefrigerant R-11Refrigerant R-113Refrigerant R-114Refrigerant R-12Refrigerant R-123Refrigerant R-124Refrigerant R-13Refrigerant R-134aRefrigerant R-152aRefrigerant R-22SteamSyltherm 800Syltherm HFSyltherm XLTSyntrel 350Thermalane 550Thermalane 600Thermalane 800Thermalane FG-1Thermalane LTherminol 55Therminol 59Therminol 66Therminol 75Therminol D-12Therminol FS, 20 wt% pgTherminol FS, 30 wt% pgTherminol FS, 40 wt% pgTherminol FS, 50 wt% pgTherminol FS, 60 wt% pgTherminol LTTherminol VP-1Therminol XPWater


DATA TABLESThe Data Tables are integral to the calculations performed by TANKJKT. They provide basic data including pipe diameters, wall thicknesses, and heat transfer coefficients for wall and lining materials.

Units conversions from US Customary to SI are listed on this worksheet. You may not change the US Customary units because all calculations are performed using these units and are dependant on them. However, the SI units just go along for the ride; you may change the label and conversion factor for them with abandon. But if you do so, please be very careful to do it correctly. Otherwise you may obtain erroneous results.

You can add additional wall or lining materials into the tables. If you have values for thermal conductivity of your material at 2 or more temperatures, regress it on a straight-line basis. A handy little table is provided (cells I37:L45) that shows how. The regression must use deg F for temperature and Btu/hr-ft-F for conductivity. After getting the regressed values for slope and intercept, insert cells into the materials or linings table and enter the values.

The diameter and wall thicknesses for half-pipe coil and internal coil pipes are contained in tables. You can change all data in these tables except for the first column, labeled "Size" which is derived from the "US Sizes" and "SI Sizes" columns.

In the cell labeled "steam coefficient" (around E82 on this worksheet) you'll find a red number. This is the coeffcient used by TANKJKT for computing the outside heat transfer coefficient for steam condensation. It is the only phase change fluid supported. As it says on the worksheet, values in the literature range from as little as 300 Btu/h-ft2-F to 1500 for steam condensing in a jacket or coil. The low value is thought to be the result of non-condensibles in the steam. Most published sources agree that 800 to 1000 is a good number to use, but you may choose any coefficient you like and enter it here.

At the bottom of this worksheet are some intermediate calculations and indices associated with the pulldown lists, checkboxes, and radio buttons found on the Data Input screen. Do not attempt to change, protect, or otherwise alter this section. It's very important to the integrity of the data and results!

Steam condensationThe heat transfer coefficient for condensing steam is set to a fixed value based on reported research.Values in the literature range from as little as 300 Btu/hr-ft2-F to 1500, with the higher values considered more accurate.The balance of opinion is to use a value in the 800 to 1000 rangeValue for steam coefficient: 900 Btu/ft²-hr-°F


CALCULATIONSCalculations are contained on the Calculation worksheet, and are arranged for easy understanding. The literature has conflicting correlations developed by different researchers over the years. Although we think the formulas used in TANKJKT represent the consensus of opinion, you are free to adjust them to your liking. The Calculation worksheet should enable you to do so without too much difficulty. However, since this is a complex spreadsheet template, exercise due caution whenever changes to calculations are contemplated.

This screen shot shows the calculation area for half-pipe coil jackets. There are similar areas for the other jacket types, internal coils, fluid data, and inside heat transfer.

The dark green shaded columns show intermediate and final results in Customary US units; the light green columns are in SI units. Whichever set of units you’ve chosen on the Data Input screen, both are displayed on the calculations sheet.

Notice the last line, “Heat transfer coefficient,” where the source of the equation used for the calculation is referenced. It is possible for you to substitute your own favorite correlation here, or make other minor changes to the code if you are so inclined.


SAVING AND RESTORING DATAIt takes time to enter all the data about a particular vessel. That’s why you have to option to save that data for reuse in the future.

Data is stored on the worksheet called “Saved Data”. When you click on the “Save Calculation” button on the Data Input sheet, the current calculation is instantly copied to the Saved Data page. You must save the entire workbook to keep access to this data for the future!

Retrieving an old calculation is simple. Choose it from the drop-down list of saved data, then click the “Restore Saved Calculation” button. That’s it.

To delete old calculations from the archive, go to the Saved Data worksheet. Then highlight the row(s) containing your unwanted data. Delete the row(s) by using Excel’s Edit…Delete… command.

The screen shot below is from the Data Input worksheet, showing the drop-down list of saved calculations. After clicking on the selection, click the “Restore Saved Calculation” button to bring it back.

TIP: Store information about commonly used classes of vessels. TANKJKT is shipped with physical dimensions of standard glass-lined vessels manufactured by Pfaudler and De Dietrich (USA). Similarly, you can add to this the types and sizes of vessels you often encounter.


REFERENCESBolliger, Donald H., “Assessing heat transfer in process-vessel jackets,” Chemical Engineering, September 20, 1982, page 95.

Bondy, Frederick, and Lippa, Shepherd, "Heat transfer in agitated vessels", Chemical Engineering, April 4, 1983, page 62.

Dream, Robert F., "Heat Transfer in Agitated Jacketed Vessels", Chemical Engineering, Vol 106, No 1, January 1999, page 91.

Garvin, John, "Understand the Thermal Design of Jacketed Vessels", Chemical Engineering Progress, Vol 95, No 6, June 1999, page 61.

Garvin, John, "Estimate Heat Transfer and Friction in Dimple Jackets", Chemical Engineering Progress, Vol 97, No 4, April 2001, page 73.

Penny, W.R., "Heat transfer correlations", in Handbook of Heat Exchanger Technology, Hemisphere Publishing Corp., New York (1983).

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TANKJKT Instructions

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