Tank Jacket Heat Transfer


Spreadsheet template that calculates heat transfer coefficients and pressure drop in jacketed tanks

$99 -- Buy Now

 TANKJKT is fast, accurate, and feature rich:

  • Simple data entry is consolidated on one screen
  • Calculates heat transfer coefficients and overall coefficient ("U")
  • Specify the flow rate, velocity or desired pressure drop for the jacket fluid
  • Creates a graph showing temperature change over time
  • Toggle between customary US or SI units of measure
  • Preformatted reports for professional presentation of results
  • Built-in databases including more than 100 different jacket fluids
  • It's a spreadsheet -- user customization is easy!

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New Features in Version 3.0

The new release retains the familiar user experience, but all of the calculations are now written in VBA which provided the developers with more flexibility. Every calculation was reviewed against the latest published correlations and algorithms. There are important new features, including::

  • Heat loss to the environment
  • Heat gain from the agitator
  • Baffle coils in addition to helical coils
  • Support for uninsulated storage tanks, with or without insulation
  • Better accuracy for tanks without agitators
  • Expanded documentation
  • Open source code - VBA macros can be reused elsewhere


TANKJKT has a large number of features. But it remains easy to use with a clear user interface. This page describes the data entry procedure, results you'll see, calculation subroutines, built-in database, and reference data.

Both SI and English (American) units are supported, and you can toggle back-and-forth between them.

A sample problem is given in the pdf document that you can download at the bottom of this page (requires Adobe Reader) It contains output from several worksheets within the TANKJKT Excel Workbook. Please look!

Easy data entry

Data input is consolidated into one worksheet. You can enter data about different types of jackets (e.g., half-pipe and baffled conventional), then play "what-if..." by toggling back-and-forth between the two. Choose your jacket fluid from the pull-down list of more than 100 fluids (and you can add your own to the database). TANKJKT calculates physical properties automatically. Input agitator information. Calculations are performed instantly.

Your data can be saved at the click of a button. Recall a previous calculation by selecting it from a drop-down list. You only have to enter physical data for a vessel one time. TANKJKT saves you time.

Data entry is grouped into seven sections:

  1. Project data. This is information that appears on the title blocks of printed reports. Your name, project name, project number, etc.
  2. Vessel data. Here you put in the vessel diameter and height. Choose the type of bottom tank head (e.g., 2:1 elliptical, hemispherical, etc.) from a list. Enter the operating volume -- TANKJKT calculates how much of the jacket is actually effective against a partially full tank.
  3. Jacket data. Data sections are provided for each type of sidewall jacket (half-pipe, conventional, dimple) and bottom head. Plus there is an entry area for internal coils. Choose any combination of sidewall, bottom head, and internal coil.
  4. Jacket Fluid. The choices are displayed in a pull-down list. You can add more compounds to the database. Input the temperature and the physical properties (thermal conductivity, density, specific heat, viscosity, and vapor pressure) are immediately displayed. You choose which method to use for determining the jacket fluid flow -- specify a flow yourself, specify a velocity in the jacket, or set the pressure drop.
  5. Vessel Fluid. Due to the unlimited combinations of fluids used in vessels, TANKJKT requires that you enter the physical properties yourself. Note: the vessel wall temperature is determined in the calculations, and TANKJKT automatically estimates the viscosity of your fluid at the wall using a published correlation.
  6. Impeller characteristics. Choose from several impeller types, or select "no impeller" then enter data such as diameter and speed
  7. Environmental conditions. Enter the outside air temperature, wind velocity, and insulation characteristics. TANKJKT calculates energy loss to the environment (or gain from it), and includes this energy in the heat transfer fluid temperature change and process fluid temperature change.

Calculates heat transfer coefficients, overall heat transfer, jacket velocity, and pressure drop

The calculations are performed in VBA subroutines that are well documented with comments. This is open-source code. If you have a proprietary correlation (for instance, there are very few correlations published for dimple jackets), you could modify TANKJKT to utilize your own formulas. That's the power of a spreadsheet! 

Reference data

Helpful pop-up comment boxes are sprinkled throughout TANKJKT to provide guidance on its use. For instance, a pop-up box appears by the "roughness" input cell, giving recommendations for values to enter. Documentation is included with full instructions on how to complete the data entry fields, and details about how the program works and can be modified with additional data


TankJkt Example (pdf)