Description
Near the Widom line, Carbon Capture and Storage (CCS) fluids, primarily carbon dioxide (CO₂) and its mixtures, display pronounced anomalies in their thermophysical behaviour. This region marks a transitional zone where the fluid undergoes rapid shifts between liquid-like and gas-like states, driven by subtle changes in temperature and pressure. As a result, key properties such as speed of sound, heat capacity, isothermal compressibility, and density exhibit sharp peaks or large variations. These fluctuations are closely linked to the underlying molecular structure and critical phenomena, making the Widom line an area of significant interest for optimising CCS processes. Understanding these property changes is essential for accurate modelling, efficient design of transport and storage systems, and ensuring the stability and safety of operations.In this communication, we present experimental methodologies, specialised equipment, and thermodynamic modelling approaches employed to investigate CO₂-rich systems in the vicinity of the Widom line. Measurements of viscosity, density, and speed of sound were performed and benchmarked against predictions from a viscosity correlation and the Multi-Fluid Helmholtz Energy Approximation equation of state. Our findings reveal that existing models exhibit significant deviations in this near-critical region compared to their performance at conditions farther from the Widom line, underscoring the need for improved formulations to accurately capture anomalous thermophysical behaviour.
| Period | 23 Jun 2026 |
|---|---|
| Event title | 23rd European Conference on Thermophysical Properties |
| Event type | Conference |
| Location | FranceShow on map |
| Degree of Recognition | International |
Keywords
- CO2
- Critical properties
- Widom Line
- Thermophysical properties