Result Changes

Pure Component Property Changes

The default density of water was changed from 997.986 kg/m³ to 999.016 kg/m³, however, existing cases and new prebuilt cases would continue on with the older value. In newer Petro-SIM versions, new case may have the new value.

Jan 2026, Bug 22318: The freeze point for n-Hexane was added to the database. This may help reduce empty freeze point properties in streams with this component.

Dec 2025: Updated TGL component boiling points.

July 2025, Bug 14520: Update RON for MTBE.

Sep 2024, Bug 20836: Starting with 7.6.7027, 7.5.6500, 7.4.4505, 7.3.3800 and 7.7 and upwards, ROM and MON values for ethanol and methanol were revised. These are now the new default values:

ComponentRonMon
Ethanol108.689.7
Methanol108.788.6

Nov 2024: Modify iso and group component properties to be consistent.

Jan 2024, Bug 16229: Updated missing RON/MON for three trimethylcyclopentane components + Corrected MON of two trimethylcyclopentane components.

Model Changes

Petro-SIM V7.7

The default new heat exchanger model is now the end point model and no longer the weighted model. This model solves more reliably.