Broad use base and number of users both in industry and academia

Friendly, prompt and professional support

Continuously developed in cooperation with leading institutes

StanMix Add-on


The StanMix Add-On offers the the iPRSV cubic equation of state for FluidProp. To use it, first download FluidProp Basic. For complete information about FluidProp, check out the FluidProp main page.

iPRSV implements a modification of the PRSV equation of state that solves the artificial discontinuity in the calculation of properties in the standard PSRV equation of state, which is relevant to some scientific and industrial applications. The PRSV cubic equation of state itself, which is implemented in the FreeStanMix model in FluidProp Basic, is one of the most accurate models to predict the properties of non-ideal gases and fluids. The accuracy of StanMix is also better than that of FreeStanMix. This feature is relevant to some scientific and industrial applications. Further advantages of StanMix  over FreeStanMix include:

  • The critical point of mixtures can be computed directly and very fast, and is much more accurate than in FreeStanMix.
  • Advanced and efficient algorithms for phase equilibria (bubble and dew point, PT-flash calculations) that avoid e.g. convergence problems close to the critical point and for mixtures with polar fluids. These algorithms also reduce computational time.

For mixtures, StanMix uses the Wong and Sandler mixing rules which are suitable for the modeling of highly non-ideal mixtures, and are thermodynamically consistent.

One of the nice features of the StanMix model is that we can easily add extra fluids to those that are already supplied.  So, even if your particular fluid is not yet available, it will not cost you much to get it into the library.

The fluids available for StanMix are listed in the fluids overview PDF file.