Particle image velocimetry measurements of a thermally convective supercritical fluid
The feasibility of particle image velocimetry (PIV) in a thermally convective supercritical fluid was investigated. Hereto a Rayleigh–Bénard convection flow was studied at pressure and temperature above their critical values. The working fluid chosen was trifluoromethane because of its experimentally accessible critical point. The experiments were characterized by strong differences in the fluid density from the bottom to the top of the cell, where the maximum relative density difference was between 17 and 42%. These strong density changes required a careful selection of tracer particles and introduced optical distortions associated with strong refractive index changes. A preliminary background oriented schlieren (BOS) study confirmed that the tracer particles remained visible despite significant local blurring. BOS also allowed estimating the velocity error associated with optical distortions in the PIV measurements. Then, the instantaneous velocity and time-averaged velocity distributions were measured in the mid plane of the cubical cell. Main difficulties were due to blurring and optical distortions in the boundary layer and thermal plumes regions. An a posteriori estimation of the PIV measurement uncertainty was done with the statistical correlation method proposed by Wieneke (Measure Sci Technol 26:074002, 2015). It allowed to conclude that the velocity values were reliably measured in about 75% of the domain.
The authors would like to acknowledge the technicians who worked on the construction and the commissioning tests of the experimental facility: Ing. Dick de Haas, Ing. Peter van der Baan, and Ing. John Vlieland. This research is supported by the Dutch Technology Foundation STW, which is part of the Netherlands Organization for Scientific Research (NWO), and which is partly funded by the Ministry of Economic Affairs.
- Adrian RJ, Westerweel J (2011) Particle image velocimetry. Cambridge aerospace series. Cambridge University Press, CambridgeGoogle Scholar
- Avdeev MV, Konovalov AN, Bagratashvili VN, Popov VK, Tsypina SI, Sokolova M, Ke J, Poliakoff M (2004) The fibre optic reflectometer: a new and simple probe for refractive index and phase separation measurements in gases, liquids and supercritical fluids. Phys Chem Chem Phys 6:1258–1263CrossRefGoogle Scholar
- Boussinesq J (1903) Théorie analytique de la chaleur, vol 2. Gauthier-Villars, ParisGoogle Scholar
- Buongiorno J, MacDonald PE (2003) Supercritical water reactor (scwr) progress Report for the FY-03 Generation-iv R&D Activities for the Development of the SCWR in the U.S. Tech. rep., INEELGoogle Scholar
- International Forum GIF (2017). https://www.gen-4.org/gif/jcms/c_9260/public
- Jackson J (2006) Studies of buoyancy-influenced turbulent flow and heat transfer in vertical passages. In: Proceedings of the annals of the assembly for international heat transfer conference 13. https://doi.org/10.1615/IHTC13.p30.240
- Karellas S, Schuster A (2008) Supercritical fluid parameters in organic rankine cycle applications. Int J Thermodyn 11(3):101–108Google Scholar
- Lemmon E, Huber M, McLinden M (2013) NIST reference database 23: reference fluid thermodynamic and transport properties-REFPROP, version 9.1. Standard Reference Data ProgramGoogle Scholar
- Pioro I, Kirillov P (2013) Current status of electricity generation in the world, vol Materials and processes for energy: communicating current research and technological developments. A. Méndez-VilasGoogle Scholar
- Pioro IL, Romney B (2016) Handbook of generation iv nuclear reactors. Woodhead publishing series in energy. Woodhead Publishing, SawstonGoogle Scholar
- Valori V (2018) Rayleigh-Bénard convection of a supercritical fluid: PIV and heat transfer study. PhD thesis, Delft University of TechnologyGoogle Scholar
- Valori V, Elsinga G, Rohde M, Tummers M, Westerweel J, van der Hagen T (2017) Experimental velocity study of non-Boussinesq Rayleigh-Bénard convection. Phys Rev E 95(053):113Google Scholar