FAQ and support

General

How do I get FlowState? FlowState 1.0 is in a controlled release. Request an invitation with the early-access form. Invited users receive download instructions for their platform.

Does FlowState need an internet connection or an account? No. FlowState runs entirely on your computer, needs no account and sends no data anywhere. The optional automation API listens only on 127.0.0.1, and only once you start it. See the privacy policy.

Why is it called “FlowState Process Studio” in the Microsoft Store? The name “FlowState” alone was already taken in the Store. It is the same application.

What file format does FlowState use? Processes are saved as .flow files, which are readable JSON. Files saved by older versions with the .spdx extension still open.

Can I use FlowState commercially? The licence covers personal, academic and internal business use. See the licence, and contact support for anything else.

Modelling

Where is the “Run” button? There isn’t one. FlowState re-simulates automatically after every change. The status bar shows how long the solve took; the toolbar status shows ✔ Solved, ⚠ Warnings or ⛔ Errors.

The recycle loop does not converge. What can I do? Open Tasks ▸ Property methods & convergence…. Raise Max iterations, switch between Wegstein and Direct substitution, or give a custom initial tear guess. You can also mark a better tear stream with Preferred tear stream in the stream’s Inspector.

Which thermodynamic model should I choose? Use Ideal (Raoult) for similar, non-polar mixtures. Use NRTL or UNIQUAC for strongly non-ideal liquids, azeotropes or two liquid phases. Use Wilson for non-ideal, fully miscible liquids. Use Peng–Robinson or SRK for gases and high pressures. See Components, mixtures and property methods.

How accurate are the cost estimates? FlowState’s equipment cost correlations are its own order-of-magnitude models, and the default cost factors are generic. For a serious estimate, enter vendor quotes or your own cost models, and adjust the factors. All results are engineering estimates that you must check before relying on them.

Why does the Economics tab say “Cost evaluation is off”? The process has no cost data, usually because it was imported from an .spf file. Enter the equipment costs and prices, then click Turn on cost evaluation. See Economics.

Where are the units settings? FlowState works in fixed SI-based engineering units: kg, °C, bar, h, m³ and $. Labels and table headers state the unit of each value.

Troubleshooting

The window is blank, or the app does not start. FlowState draws with the GPU. Update your graphics driver. On Linux, check that the Vulkan or OpenGL drivers for your GPU are installed.

Excel cannot reach the automation API. Make sure the server is running (Tools ▸ Start automation server, or flowstate-cli serve). Use http://127.0.0.1:8765 in the URL rather than a host name. Browser-based tools such as Office Scripts also need their origin allowed. See Command line and automation API.

An imported .spf file gives warnings. The warnings are listed in the process notes. See Importing .spf project files.

Support

E-mail support@yaylali.uk. To help us answer quickly, include:

• your FlowState version (shown in Help ▸ About FlowState) and operating system;
• what you did, what you expected, and what happened;
• if you can share it, the .flow file, or a cut-down version that shows the problem.

FlowState is developed by Kemal Yaylali (kemalyaylali.bio).