Flowstead v3.1.0

Flowstead v3.1.0 (app version 3.1.0).

DWSIM files, petroleum assays, black oil and thermodynamics tools

• DWSIM files keep more. Pipe segments can be made of several runs and fittings (DWSIM's 28: elbows, valves, tees, entrances, exits, reducers), edited in the pipe segment, shown on its profile and data sheet, and read from DWSIM files instead of being merged into one straight pipe. Adjusts, controllers and Sets are written to DWSIM files and read back. Streams given by pressure and entropy import, and the engine's own energy streams no longer appear after a round trip.
• Petroleum assays. Fluid package → Characterise an assay: a TBP, ASTM D86, D1160 or D2887 curve with the bulk SG and MW and light ends, or a plus fraction from its bulk properties, cut into pseudo-components. They become hypotheticals, and a new stream gets the assay's composition. The D86 conversion matches the API Technical Data Book's example within 0.3 °F.
• A stream's distillation curves. In the stream editor: TBP, D86, D1160, D2887 and EFV curves and product properties (flash, pour, cloud and freezing points, cetane index, Reid vapour pressure and more, by the API correlations).
• Black oil. A new Black Oil fluid package: add a black oil from its API gravity, gas gravity, GOR and water cut. DWSIM's own black-oil code is corrected in Flowstead's build: the oil now keeps its gas above the bubble point and gets denser with pressure, and the gas and oil flows add up to the stream's. Densities and liberated gas match Standing's and Vasquez–Beggs' correlations worked by hand.
• Thermodynamics tools. Fluid package → Thermodynamics tools: binary T–x–y and P–x–y diagrams (with the region where two liquids form), ternary diagrams with tie lines, the true critical point, up to eight fluid packages compared on one composition, and property charts along temperature or pressure. Checked against NIST boiling points, vapour pressures and critical constants.
• Fixed: when every controller already met its target (as in a file saved solved), the solve showed the numbers of a test step instead of the solution.

Install: download flowstead-v3.1.0.apk on your Android phone (Android 8.0 or newer, 64-bit), open it and allow installing from this source.

Coming from a 0.x test build? Those were signed with the public debug key and this release is signed with the release key, so Android can't install it over them: export each project you want to keep (project menu → Export DWSIM file), uninstall the old app, install this one and import the files (Projects → Import DWSIM file). Data-sheet fields and line-sizing criteria are not part of a DWSIM file. Later releases install as updates.

Solves on the phone: DWSIM runs on the device (Settings → Engine → On this phone, the default); the first solve after starting the app takes a few seconds while DWSIM loads. A remote Flowstead engine (docs/engine-setup.md) is optional.

Release certificate SHA-256: d7883cfc24f1cb62db989086d69d217beed109b5b84164ff5394ad9e3e0bb921. flowstead-v3.1.0-mapping.txt de-obfuscates crash reports. Status and known limitations: docs/STATUS.md.

Commit: 83af9b4