Supercritical carbon dioxide (sCO2) can be mixed with dopants such as titanium tetrachloride (TiCl4), hexafluoro-benzene (C6F6), and sulphur (SO2) to raise the critical temperature of working fluid, allowing it condense at ambient temperatures in dry solar field locations. The resulting transcritical power cycles have lower compression work higher thermal efficiency. This paper presents aerodynamic flow path design a utility-scale axial turbine operating an 80–20% molar mix CO2 SO2....

This work focuses on the off-design analysis of a simple recuperative transcritical power cycle working with CO2+C6F6 mixture as fluid. The is air-cooled and proposed for state-of-the-art concentrated solar plant salts heat transfer fluid in hot region, minimum maximum temperature 51 °C 550 at design conditions. each exchanger (primary, recuperator condenser) carried out MATLAB referenced models turbine designed CFD, providing performance maps adopted by operating sliding pressure. developed...

Abstract Within this study, the blade shape of a large-scale axial turbine operating with sCO2 blended dopants is optimized using an integrated aerodynamic-structural three-dimensional (3D) numerical model, whereby optimization aims at maximizing aerodynamic efficiency whilst meeting set stress constraints to ensure safe operation. Specifically, three candidate mixtures are considered, namely, CO2 titanium tetrachloride (TiCl4), hexafluorobenzene (C6F6), or sulfur dioxide (SO2), where...

The dry-cooled Rankine cycle working with a zeotropic mixture of CO2+C6F6 is influenced by the ambient temperature as air used heat sink. Varying sink temperatures allow for operating under sliding condensation pressure which may benefit hybrid PV-CSP plant. study demonstrates effect this operation mode on composition shift and investigates performance. results show that defining turbine design conditions significantly impact whether system´s thermodynamic performance behaves acceptably in...

This paper presents an investigation of the aerodynamic performance a 130 MW axial turbine operating with CO2/SO2 mixture using mean-line off-design model; where validity this model has been confirmed through verification against results from literature and computational fluid dynamic (CFD) simulations. analysis also includes assessing impact varying number stages on part-load operation. Additionally, application similitude theory to non-dimensionalise characteristics is validated by same...

Abstract A detailed loss assessment of an axial turbine stage operating with a supercritical carbon dioxide (sCO2) based mixture, namely titanium tetrachloride (CO2-TiCl4 85-15%), is presented. To assess aerodynamic losses, computational fluid dynamics (CFD) simulations are conducted using geometry generated mean-line design equations which part the work delivered to SCARABEUS project [1]. The CFD 3D steady state and employ number turbulence models investigate various mechanisms. Two...

Abstract In this paper, a modified loss breakdown approach is introduced for axial turbines operating with supercritical carbon dioxide (sCO2) mixtures using computational fluid dynamics (CFD) results. Loss analysis has been previously developed two approaches, however each its own uncertainties. The first neglects the effects of cross-interaction between different sources, while second ignores potential changes to boundary layer thicknesses and source domains. Although methodology accounts...

Abstract In this paper, the design of a large-scale axial turbine operating with supercritical carbon dioxide (sCO2) blended sulfur (SO2) is presented considering aerodynamic and mechanical aspects as well integration whole assembly. The shaft power 130 MW, designed for 100 MWe concentrated-solar plant inlet conditions 239.1 bar 700 °C, total-to-static pressure ratio 2.94, mass-flow rate 822 kg/s. flow path, obtained in previous study, first summarized before performance evaluated using both...

Abstract In this paper, the design of a large-scale axial turbine operating with supercritical carbon dioxide (sCO2) blended sulfur (SO2) is presented considering aerodynamic and mechanical aspects as well integration whole assembly. The 130 MW, designed for 100 MWe concentrated-solar power plant inlet conditions 239.1 bar 700 °C, total-to-static pressure ratio 2.94 mass-flow rate 822 kg/s. flow path, obtained in previous study, first summarised before performance evaluated using both...

Abstract Within this study, the blade shape of a large-scale axial turbine operating with sCO2 blended dopants is optimised using an integrated aerodynamic-structural 3D numerical model, whereby optimisation aims at maximising aerodynamic efficiency whilst meeting set stress constraints to ensure safe operation. Specifically, three candidate mixtures are considered, namely CO2 titaniumtetrachloride (TiCl4), hexafluorobenzene (C6F6) or sulfur dioxide (SO2), where selected blends and boundary...