Alph - A Little Process Helper

Getting Started

With this series of short tutorials, I hope to introduce the key features of Alph. If possible, follow along on your own iPhone (whenever I use the term iPhone, you can substitute iPod Touch or iPad as appropriate). Only compounds and features available in the base version of Alph and in Alph Jr. are used.

Each tutorial section builds on the previous one, so it is best to go through them in series. However at the start of each one, there will be a link to a completed case file for the previous section should you wish to skip over some:

Note Alph is an evolving program and replacing screenshots is tediious, so there maybe be some minor differences between the page views in the application and the screenshots in some parts of this tutorial. Most of the images in this tutorial come from an iPhone, which being smaller fit better on a web page. An iPod Touch will have the same appearance, but on an iPad, the pages will be similar, but will display in windows over top of the information flow diagram, with arrows pointed at the object of interest.

iPhone/iPod Touch iPad
Screenshot   Screenshot

This is the Alph Session Menu page and is the starting point for any new session. If this is not the page you see, tap the button in the upper left of the screen until this page appears.

Note if you are running Alph Jr, the Property Package and Alph Store lines won't appear.

Tapping on any of the white bars with a > at the right will take you to the page designated by its label.

Try tapping on the Case line.
(Note that tutorial lines in green indicate an action that will take you to the next screen shot).


This page has a number of options having to do with cases, such as saving your work and loading different sessions.

For now just tap the New Case line.


This alert warns you that you are about to replace any current work, presumably none in this case, with a new empty case.

Go ahead and tap OK.


We have simply returned to the session menu.

Continuing our tour of the session menu, note the switch on the US Units line. By default Alph works in metric units, but you can switch to US units (pounds, BTU etc.) any time you wish by flipping this switch.

Tap the Displayed Properties line on the session menu to bring up the page where you can select which properties are displayed for fluids.


Properties selected for display will have a check mark on the right side of their line. You toggle this status by just tapping on the line. Note that these selections only affect the display of fluids. You can access any of these properties from formulas, which will be discussed later, whether they are being displayed or not.

Alph uses the common usage single and double character abbreviations for the most common properties as this makes including them in formulas easy. If you are unsure of the meaning of any of the abbreviations, tap the help button (?) at the right of the lower tool bar for definitions.

Note that every page has a help button which will provide a short explanation of that page.

Tap the Session button to return to the session menu. In general this button at the upper left of each page will take you up a level in the page hierarchy. If titled Cancel it will leave the current page ignoring any changes that might have been made.


Most cases will actually start by selecting the compounds to be used.

Tap the Compounds line.


Note that the buttons at the bottom of the window have changed to Library, Families and Installed. More about those in a minute, but for now notice that we are currently on the Library page and its button is greyed out.

To install a compound into the case, simply tap its line. Like the displayed properties, selected compounds will have a check mark to the right and tapping a selected compound will deselect it. When you select a new compound it will be added to the end of the list of compounds to install.

The compounds listed will depend on what additional options you have purchased and on the currently displayed compound family. By default this will be the Common family.

For this tutorial, select the normal paraffins methane through octane in order, and then tap the Installed button on the bottom toolbar.


This shows the compounds that will be installed when you tap the Save button. The order of the compounds will depend on the order in which you selected them on the Library page, but you can change the order if you wish.

Tap on any compound name. (The custom compound line is only available as an option).


Each compound line now has a delete icon (the red circle at the left (and a move icon (the triple grey bars at the right). Tap one of the move icons and hold until the line is highlighted. You can now drag the compound to the desired location in the list. You can also remove a compound from the list by tapping the delete icon and then the resulting Delete button. You can also get the delete button without entering this edit mode, by just swiping sideways on a compound or deselecting it from the Library page.

Note that once we entered the reorder mode, the Installed button became enabled again. Simply tap it to exit the reorder mode.

For completeness, tap the Families button before we leave the compound selection.


Unless you have the Alph Professional option, only the first two lines will appear.

The Common family is the default and includes all installed compounds except those only available in the much larger professional library.

The Starts With family will display a text field where you can enter the first few characters of a compound and then the Library page will only display matching compounds.

Once you have the compounds selected and in the order you want, tapping the Save button at the upper right of the page will actually install the compounds in the case. Note that if you tap the Cancel button at the upper left instead, no changes to the installed library compounds will take place.

You can return to this page later and add, delete or reorder compounds as you wish. You do need to consider the implications this may have for any fluid compositions that you have specified. The compositions will be retained and supplied in the same order to the new compound list. Extra specifications will be ignored and zeros supplied for missing ones.

Tap the Save button.


Back at the session menu, you will see that there is now an '8' on the right of the Compounds line. This indicates that there currently are 8 compounds included in the case. If you see a different number, return to the compounds page and ensure that you have selected methane, ethane, propane, n-butane, n-pentane, n-hexane, n-heptane and n-octane.

Tap the Fluids button on the bottom tool bar to go to the fluids page.


Well that is dull! Note that the left most button on the tool bar has changed to New.

Tap it to create a new fluid.


A fluid has been created and the input page for it is being displayed. Alph has creatively named the new fluid 'f1', but lets change it to something more meaningful.

Tap the greyed 'x' on the right of the name field to erase Alph's suggestion.


Type in the name feed. Note that the names of fluids, variables and tools in Alph are not case sensitive, so you could name this fluid 'Feed' and refer to it later as 'feed'.

Tap in the temperature field and enter 10 and in the pressure field and enter 4000.

Note that if you just enter a number in a field, the appropriate default unit will be appended for you. This will be retained even if you change unit sets in the future. The current default unit set is displayed in the button at the right of the title bar and can be toggled to the other set by tapping the button.

Now tap the blue arrow icon at the right of X (molar composition) field.


This will bring up the composition input page. The switch on the top can be set if you want the sum of the inputs to be automatically assigned as the molar flow of the fluid - handy if you have the composition in molar flows.

Compositions are always normalized for use in the property package, so you can specify the composition in mole percent or mole flows and the correct composition in mole fractions will be calculated.

Leave it off for this example.


Enter the following values into the designated fields:


Tap Done and then Save to return to the Fluid input page.


The X field has been filled in with the string [ 70,20,10,9,8,7,6,5 ], which represents your composition input in array format. These input fields are actually formula fields (more about that later) and the square bracket notation designates an array.

Up until now I have been ignoring the buttons on the tool bar at the bottom of the page. These represent various ways of viewing the fluid on this page.

We have been using the Input view up to this point, but now tap the Bulk button to see the fluid's mixed phase properties.


You can see that the flashed fluid is about 53 percent vapour and the enthalpy (H) and the entropy (S) values have been determined for the combined phases. If we had checked additional properties on the Displayed Properties page, these would be shown as well.

The flow rate is unknown however, so let's return to the input view and rectify that.

Tap on the Input button at the left of the bottom tool bar.


Tap in the Flow field and type in 10 mmscfd. In this case we are explicitly giving a unit, which will be retained regardless of future changes we might make to the default units.

Tap on Done and then the Bulk button again to see the result.


The flow is now filled in.

You might find the units on enthalpy unusual when using metric units. These are in W-hr/kgmole rather than the more common kJ/kgmole. This is to provide consistency in equation calculations we shall be discussing in coming parts of this tutorial. Essentially the convenience of being able to say delta H times flow equals Q without worrying about a conversion factor, far outweighs the need to divide by 3.6 for the very few people who are actually interested in knowing specific enthalpy values in kJ/kgmole.

If you wish to change the properties displayed for fluids, remember that you can do so from the Displayed Properties page that you can access from the session menu.

Tap on the Vap button to see the vapour properties.


The array form of the composition isn't exactly reader friendly, so tap on the X line to bring up a more readable display of the composition.


The composition results page also has buttons that allow you to switch phase views.

Tap the Liq button to switch to the liquid composition.


Tap the Properties button at the upper left to move back to the main fluid page.


Liquid remains as the subject even as we return to the properties view.

Tap on the Back button (it may say Fluids) to return to the fluid list page.


Our fluid now appears in the list, but it is still a pretty dull page. In a future tutorial, when we have some additional fluids, we shall see how to delete fluids and rearrange the list.

Tap on the button on the upper left to return to the session menu and then tap the Case button.


Alph automatically saves the current case whenever you leave the program and restores it when you return, but it is still a good idea to save your case explicitly.

Tap the Save Case line.


Enter "tutorial" or a name of your choice into the Name field and tap the Save button at the upper right.

Once a case has been named, then tapping the Save Case line on the Case page will immediately save the case to that file. An iPhone or iPod Touch will vibrate briefly to acknowledge your request. You can use the Save Case As line on the session menu to return to this screen and save the case in a different file.

The Save to Paste Board button will cause the case to be written to the paste board (Apple's name for the clipboard). A case is simply all the input required to recreate the case written in a plain text format (JSON for the web savvy).

There is a corresponding Load from Paste Board button on the Load Case page, so you can copy a case from an email message or web page or whatever and recreate it on your phone. In this way you can share cases with other users or save them on a different computer.

As a convenience, there is also a Mail Case button, which will open a compose mail screen with the body of the message already filled in with the case file text.

This is probably a good point to split things up, so please go the next tutorial section.