PVTsim is developed by PVT specialists, but you do not need to be a specialist to make qualified use of PVTsim. Follow the recommended workflow and in a short time you will have the interface file you are after for a reservoir, flow or process simulator. PVTsim also offers PVT specialists the flexibility they require to lumping options, model selection and handling of complex phase equilibria, possibly including solid phases. Further down on this page we highlight key features in more detail.

Automated Input of PVT Data

PVTsim supports the PRODML 2.1 format by Energistics (energistics.org). PVT reports in PRODML 2.1 XML format are automatically imported into PVTsim. The data format covers:

• Bottom Hole Samples
• Separator Samples
• Oil Based Mud Compositions
• Classical Plus Fluid Compositions
• Extended Gas Chromatography to e.g. C₃₆₊
• Routine PVT and EOR Data
  • Atmospheric Flash Test
  • Saturation Point
  • Separator Test
  • Constant Mass Expansion
  • Constant Volume Depletion
  • Differential Depletion
  • Swelling Test including CME and Viscosity Data
  • Viscosity Data

Calsep’s Excel PVT Format is another option for automated input of PVT data. A PVT report in Calsep Excel PVT Format can be imported into PVTsim in one click.  Four different templates are installed with PVTsim and support the above types of fluid compositions and PVT data. The templates support both metric, field and SI units

EoS Modeling Single Fluids

An equation of state (EoS) model for a reservoir fluid to be produced is a prerequisite for  a qualified planning of the production and for an optimal design and operation of the production equipment.

PVTsim’s Auto EoS has more than 35 years of built-in experience. It enables users without specialist knowledge of PVT modeling to develop quality EoS models within minutes. The Auto EoS option performs a quality check of fluid compositions and PVT data and informs the user of possible inconsistencies. It suggests an appropriate lumping scheme and the weights to be assigned to the different types of PVT data to be matched, but allows the user to change the suggested settings.

Users with more experience in EoS modeling can use PVTsim’s options for Plus regression and Characterized regression. Plus regression is an assisted regression method that in a physically reasonable way changes how the EoS parameters of the C7+ components change with molecular weight. Characterized regression allows the user full freedom to change EoS parameters for all components as well as to tune on the binary interaction parameters.

Bottom hole samples will often be contaminated by drilling mud. In such cases, the mud will affect the PVT data measured for the fluid. PVTsim’s Clean for Mud module can not only perform a numerical cleaning of the fluid. It can also develop an EoS model for the clean reservoir fluid, taking into account the PVT data for the contaminated fluid.

PVTsim supports the SRK and PR (76 and 78 modifications) industry standard state equations of state, with and without volume correction. The volume correction can be made temperature dependent, which especially for heavy oils may be appropriate. Cubic equations may have difficulties predicting the isothermal compressibility of oils. Therefore, PVTsim  offers the PC-SAFT equation as an alternative to the above-mentioned cubic equations. The PC-SAFT equation is developed primarily for polymer systems for which a correct prediction of compressibility is crucial.

PVTsim Nova 5.3 to 5.4