Robust integration of real gas models into a pressure-based coupled solver

Today’s most common standard for compressible computational fluid dynamics is based on the ideal gas state equation. However, real gas modeling is fundamental for a wide range of applications. When expanding into the thermodynamic region of non-ideal gas, performance predictions based on ideal gas assumption are no longer valid. Therefore, more accurate models are desired for an improved classification of fluid properties. While there is a wast amount of literature about possible improvements when using real gas state equations in a numerical framework, little is known considering the actual implementation. This article will therefore focus on the robust integration of real gas flow physics in an in-house, coupled, pressure-based solver. We will point out the main difference to a numerical framework purely based on perfect gas. Final validation is given using a two stage radial compressor setup to demonstrate the generality of the chosen approach.