Thermo-economic optimization and part-load analysis of the combined supercritical CO2 and Kalina cycle

http://manuscript.elsevier.com/S0360544222009562/pdf/S0360544222009562.pdf

Topology optimization of heat exchangers: A review

One-dimensional optimisation design and off-design operation strategy of centrifugal compressor for supercritical carbon dioxide Brayton cycle

On a ten-year timescale, Carbon Capture and Storage could significantly reduce carbon dioxide (CO2) emissions. One of the major limitations of this technology is the energy penalty for the compression of CO2 to supercritical conditions, which can require up to 15% of the plant’s gross power output. To reduce the power requirements supercritical carbon dioxide compressors must operate at reduced temperatures and near saturation where phase change effects are important. Nonequilibrium condensation can occur in the high-speed flow at the leading edge of the compressor, causing performance and stability issues. The characterization of the fluid at these conditions is vital to enable advanced compressor designs at enhanced efficiency levels but the analysis is challenging due to the lack of data on the metastable fluid properties. In this paper we assess the metastable behavior and nucleation characteristics of high-pressure subcooled carbon dioxide during the expansion in a Laval nozzle. The assessment is conducted with numerical calculations, supported and corroborated by experimental measurements. The Wilson line is determined via optical measurements in the range of 41 and 82 bar and near the critical point. The state of the metastable fluid is fully characterized through pressure and density measurements, with the latter obtained in a first of its kind laser interferometry set up. In a systematic analysis the inlet conditions of the nozzle are moved close to the critical point to allow for large gradients in fluid properties and reduced margin to condensation. The results of calculations using a direct extrapolation of the Span and Wagner equation of state model are compared with the experimental measurements. The analysis suggests that the direct extrapolation using the Span and Wagner model yields results within 2% of the experimental data, with improved accuracy at conditions away from the critical point. The results are applied in a pre-production supercritical carbon dioxide compressor and are used to define inlet conditions at reduced temperature but free of condensation. Full-scale compressor experiments demonstrate that the new inlet conditions can reduce the shaft power input by 16%.

Characterization of Non-Equilibrium Condensation of Supercritical Carbon Dioxide in a de Laval Nozzle

Off-design behavior investigation of the combined supercritical CO2 and organic Rankine cycle

Zwitterionic ionic liquids (ZIL) contain covalently bound cationic and anionic moieties with potential electrochemical applications. In this study, we construct a self-adaptive electric double layer (EDL) on the interfaces of...

Yadong Du

Papers

Engineering Self-adaptive Electric Double Layer on Both Electrodes for High-Performance Zinc Metal Batteries

One-dimensional optimisation design and off-design operation strategy of centrifugal compressor for supercritical carbon dioxide Brayton cycle

Thermoeconomic analysis and inter-stage pressure ratio optimization of nuclear power supercritical CO2 multi-stage recompression

Thermodynamic design and Off-design investigation of nuclear power supercritical CO2 recompression cycle

Size optimization of heat exchanger and thermoeconomic assessment for supercritical CO2 recompression Brayton cycle applied in marine