Experimental Facilities for Non-Ideal Compressible Vapour Flows

The experimental characterization of non-ideal compressible flows of vapours at thermodynamic conditions close to the saturation curve and the critical point raised considerable interest in the last decade, in both industry and scientific community. The main motivation was the need to validate the tools employed for the design and the analysis of components implementing such flows, which are typically turbomachines, valves, nozzles, diffusers, and pipelines. These tools are based on Computational Fluid Dynamic (CFD) codes specifically conceived for non-ideal flows, whose assessment demands for accurate experimental data, featuring a spatial resolution comparable with the one achievable through numerical simulations. Industrial plants are unsuited to this objective, due to their intrinsic limitation in accessibility for instruments, availability, and operational flexibility, which are typically required by experiments. This brought researchers to design and implement test rigs dedicated to detailed fluid dynamic investigation of non-ideal vapour flows. The facilities existing worldwide for investigation of non-ideal compressible vapour flows are reviewed here. Their configuration and main features are discussed, together with their capabilities in terms of testable flows. Finally, illustrative results obtained up to date are shown for each facility.