Analysis on thermodynamic and economic performances of supercritical carbon dioxide Brayton cycle with the dynamic component models and constraint conditions

Using supercritical carbon dioxide (SCO2) as the working fluid of a closed Brayton cycle gas turbine is widely recognized nowadays, because of its compact layout and high efficiency for modest turbine inlet temperature. It is an attractive option for geothermal, nuclear and solar energy conversion. Compressor is one of the key components for the supercritical carbon dioxide Brayton cycle. With established or developing small power supercritical carbon dioxide test loop, centrifugal compressor with small mass flow rate is mainly investigated and manufactured in the literature; however, nuclear energy conversion contains more power, and axial compressor is preferred to provide SCO2 compression with larger mass flow rate which is less studied in the literature. The performance of the axial supercritical carbon dioxide compressor is investigated in the current work. An axial supercritical carbon dioxide compressor with mass flow rate of 1000kg/s is designed. The thermodynamic region of the carbon dioxide is slightly above the vapor-liquid critical point with inlet total temperature 310K and total pressure 9MPa. Numerical simulation is then conducted to assess this axial compressor with look-up table adopted to handle the nonlinear variation property of supercritical carbon dioxide near the critical point. The results show that the performance of the design point of the designed axial compressor matches the primary target. Small corner separation occurs near the hub, and the flow motion of the tip leakage fluid is similar with the well-studied air compressor. Violent property variation near the critical point creates troubles for convergence near the stall condition, and the stall mechanism predictions are more difficult for the axial supercritical carbon dioxide compressor.

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Thermodynamic analysis and optimization of the combined supercritical carbon dioxide Brayton cycle and organic Rankine cycle‐based nuclear hydrogen production system

International Journal of Energy Research ◽

10.1002/er.7208 ◽

2021 ◽

Author(s):

Qi Wang ◽

Chunyu Liu ◽

Run Luo ◽

Dantong Li ◽

Rafael Macián‐Juan

Keyword(s):

Carbon Dioxide ◽

Hydrogen Production ◽

Supercritical Carbon Dioxide ◽

Thermodynamic Analysis ◽

Production System ◽

Organic Rankine Cycle ◽

Rankine Cycle ◽

Brayton Cycle ◽

Supercritical Carbon

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Advanced Supercritical Carbon Dioxide Brayton Cycle Development

10.2172/1226260 ◽

2015 ◽

Author(s):

Mark Anderson ◽

James Sienicki ◽

Anton Moisseytsev ◽

Gregory Nellis ◽

Sanford Klein

Keyword(s):

Carbon Dioxide ◽

Supercritical Carbon Dioxide ◽

Brayton Cycle ◽

Supercritical Carbon

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Supercritical Carbon Dioxide Heat Transfer in Horizontal Semicircular Channels

Journal of Heat Transfer ◽

10.1115/1.4006108 ◽

2012 ◽

Vol 134 (8) ◽

Cited By ~ 26

Author(s):

Alan Kruizenga ◽

Hongzhi Li ◽

Mark Anderson ◽

Michael Corradini

Keyword(s):

Heat Transfer ◽

Carbon Dioxide ◽

Heat Exchanger ◽

Supercritical Carbon Dioxide ◽

Turbulent Heat Transfer ◽

Turbulent Heat ◽

Brayton Cycle ◽

Heat Exchanger Design ◽

Transfer Behavior ◽

Supercritical Carbon

Competitive cycles must have a minimal initial cost and be inherently efficient. Currently, the supercritical carbon dioxide (S-CO2) Brayton cycle is under consideration for these very reasons. This paper examines one major challenge of the S-CO2 Brayton cycle: the complexity of heat exchanger design due to the vast change in thermophysical properties near a fluid’s critical point. Turbulent heat transfer experiments using carbon dioxide, with Reynolds numbers up to 100 K, were performed at pressures of 7.5–10.1 MPa, at temperatures spanning the pseudocritical temperature. The geometry employed nine semicircular, parallel channels to aide in the understanding of current printed circuit heat exchanger designs. Computational fluid dynamics was performed using FLUENT and compared to the experimental results. Existing correlations were compared, and predicted the data within 20% for pressures of 8.1 MPa and 10.2 MPa. However, near the critical pressure and temperature, heat transfer correlations tended to over predict the heat transfer behavior. It was found that FLUENT gave the best prediction of heat transfer results, provided meshing was at a y+ ∼ 1.

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