© 2024 Jasper van Baten, AmsterCHEM

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Welcome to the Excel CAPE-OPEN unit operation. This is a steady-state CAPE-OPEN unit operation that allows you to do calculation in Microsoft Excel. A CAPE-OPEN unit operation can be plugged in to CAPE-OPEN compliant simulation environments. Main-stream process simulators have support for CAPE-OPEN. As an example, you can use this unit operation in the free CAPE-OPEN flowsheet simulator COCO.

To get started, insert the unit operation into a CAPE-OPEN based flowsheet environment. Then, edit the unit operation. Excel will open allowing you to edit the spread sheet that defines the unit operation's calculations.

On the *feeds* sheet, you can add and remove material feed streams. On the *products* sheet, you can
add or remove product streams. Similarly, you can add and remove in- and output parameters
on the *input parameters* and *output parameters* sheets.

To define a working unit operation, you will need to specify formulas that calculate the product streams and output parameters. At this point it is useful that the unit operation knows about the thermodynamics. It only knows this once you have connected at least one stream to a feed or product port. So now that you have configured feed and product ports, close Excel and return to the simulation environment. At this point, connect one or more streams to the unit operation. Make sure that thermodynamic have already been configured in the simulation environment, so that the streams will tell the unit operation about which chemical compounds are present.

Go back to editing the unit. Excel will re-open. At this point you should see the feed
conditions, as far as they have been specified. The *feeds* and *products* sheets will also
list the compounds that are present.

For each product, you will need to specify formulas to calculate the *product* stream. Specify
a formula for the stream's composition and the total flow. Also, 2 out of 3 of pressure,
temperature and enthalpy must be specified; two specifications of these variables are
requires in order for the unit operation to be able to calculate the thermodynamic equilibrium.

You can also at this point specify formulas to calculate the output parameter values.

In your formulas, you can use functions for thermodynamic calculations. A short summary
of these functions is provided on the *control* sheet. This sheet also allows you to inspect
which thermodynamic properties and phases are supported. Click the appropriate button
for more information.

To access this help from with Excel, click the Help button on the Unit Operation ribbon.

The Excel CAPE-OPEN Unit Operation requires a working version of Microsoft Excel, version 2010 or higher, to be installed at your system.

The Excel unit operations requires User Defined Functions (UDFs). These are stored in the AmsterCHEM Excel CAPE-OPEN Unit Operation UDF Add-In, which is by default installed and activated. Without this Add-In, the calculations will not work properly. To make sure the Add-In is installed and active, click Excel Options from the Office menu, go to the Add-Ins tab, select to manage Excel Add-Ins:

If the Add-In is not registered, please re-install the Excel CAPE-OPEN Unit Operation software.

Also shown in the above is the Excel Solver Add-in, which may come in handy for solving non-explicit equations. If the solver is not available, you can located it from the Excel library folder using Browse.

Your Excel model is saved as xlsx file, which means you cannot use Macros in your Excel book. If you need to use Macros, you need to supply your own XLS add-in (e.g. a .xlam file).

If you have saved your unit operation using Excel 2010, the next time you open it on a different machine, you may find that the reference to the Add-In has not been stored properly. Excel may ask you to do something about it when opening the document:

Please answer No; the Excel Unit Operation will fix the links immediately after loading the workbook.

If you are loading the Excel unit Operation on a different system with Excel 2010, you may get warned about something similar to:

Please answer Disable; the Excel Unit Operation will fix the links immediately after loading the workbook.

Once a fixed workbook is stored, the messages will no longer appear.

The Excel CAPE-OPEN unit operation was developed by AmsterCHEM.

Micosoft Excel and VBA are registered trademarks of Microsoft Corporation in the United States and other countries.

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