We’re excited to announce a major expansion in CHEMCAD simulation accuracy: the integration of REFPROP into the CHEMCAD user interface.
With the newest release of CHEMCAD NXT (version 1.2.0), REFPROP is available as a built-in thermophysical property calculator, allowing users to seamlessly switch between CHEMCAD’s default models and REFPROP’s high-fidelity calculations for pure fluids and mixtures. This integration brings new levels of precision to simulations involving refrigerants, natural gas blends, and supercritical fluids without requiring separate installation or licensing.
REFPROP is an advanced database and calculation tool developed by the National Institute of Standards and Technology (NIST) for the accurate prediction of thermophysical properties. Despite often being referred to as a “database,” REFPROP is technically a calculation engine that uses highly detailed equations to calculate thermodynamic and transport properties. These detailed equations are considered to be the most accurate available worldwide, trusted in both industry and academia.
With the integration of REFPROP, CHEMCAD offers expanded capabilities for cases where REFPROP provides higher accuracy prediction for thermophysical properties. This flexibility allows users to select the best tool for the job, whether optimizing refrigeration cycles, evaluating low-GWP refrigerants, or designing supercritical CO₂ systems.
Integrating REFPROP into CHEMCAD brings powerful advantages for engineers modeling complex fluids and mixtures. While unmatched in its precision for fluid property calculations, REFPROP is not universally applicable. As with any model, its effectiveness depends on the context and process requirements.
Here's what to expect when using REFPROP within CHEMCAD:
Understanding REFPROP’s strengths and limitations helps engineers choose the right property model for their simulation goals, balancing accuracy with performance and feature availability.
Supercritical CO₂ systems are a prime example of where REFPROP adds significant value to CHEMCAD simulations. Supercritical CO2 is important in power generation, carbon capture, refrigeration, and chemical extraction, where accurate property prediction is essential for performance and safety.
Traditional models often struggle at extreme process conditions, leading to errors in density, phase behavior, and equipment sizing. REFPROP provides significantly better alignment with experimental data, especially at low temperatures and high pressures.
Engineers can use CHEMCAD to run sensitivity analyses, compare results to equation-of-state models, and optimize designs with greater confidence. This level of accuracy is especially valuable for:
By using REFPROP in CHEMCAD, engineers can reduce uncertainty, improve reliability, and make better-informed design decisions for systems operating near or above the critical point.
To access REFPROP, users must upgrade to CHEMCAD version 1.2.0 or later, where the integration is available directly within the CHEMCAD interface. Once installed, navigate to the Thermophysical tab in the command ribbon, where you’ll find a new section labeled Library. This is where you can switch between CHEMCAD’s traditional property library and the REFPROP calculation engine.
Before switching, make sure your flowsheet meets the minimum criteria. The Component Selection dialog after switching looks familiar, but only displays REFPROP’s pure components and does not allow user-defined chemicals, solids, electrolytes, or petroleum assays.
To learn more about REFPROP’s capabilities and limitations, click the Help button within the CHEMCAD interface or reach out to the CHEMCAD support team for guidance. Whether you rely on traditional models or switch to the REFPROP engine, you can rely on CHEMCAD’s simulation capabilities built for accuracy, flexibility, and performance.