TY - GEN
T1 - Numerical method for simulating high pressure CO2 flows with nonequilibrium condensation
AU - Furusawa, Takashi
AU - Miyazawa, Hironori
AU - Moriguchi, Shota
AU - Yamamoto, Satoru
PY - 2018/1/1
Y1 - 2018/1/1
N2 - A numerical method for compressible flows withnonequilibrium condensation is reconstructed for simulatingsupercritical CO2 flows with nonequilibrium condensationunder high pressure conditions. Thermophysical propertiesare interpolated from pressure-temperature look-up tables anddensity-internal energy look-up tables, which are generatedusing the polynomial equations in REFPROP. We employ thehigh pressure nonequilibrium condensation model in which thecritical radius of a liquid droplet is modified by consideringnon-ideal gas. We simulate high pressure CO2 flows through aLaval nozzle, which was experimentally investigated byLettieri et al. High-pressure CO2 passes through the nozzle,leading to a decrease in its pressure and temperature. It reachesthe supercooled condition near the throat. Nucleation and thesubsequent growth of droplets lead to an increase in thecondensate mass fraction in the diverging area. The proposedmethod for real gas reproduced the peak of pressuredistribution owing to the release of latent heat, whereas thenumerical result assuming ideal gas is different from theexperimental result. The nucleation region obtained using thepresent method is earlier and narrower than that in the case ofideal gas. The early and rapid nucleation leads to the high masscondensate rate at the outlet. These results show thatconsidering the real gas effect and nonequilibriumcondensation is crucial for developing the impeller of acompressor for the supercritical CO2 Brayton cycle.
AB - A numerical method for compressible flows withnonequilibrium condensation is reconstructed for simulatingsupercritical CO2 flows with nonequilibrium condensationunder high pressure conditions. Thermophysical propertiesare interpolated from pressure-temperature look-up tables anddensity-internal energy look-up tables, which are generatedusing the polynomial equations in REFPROP. We employ thehigh pressure nonequilibrium condensation model in which thecritical radius of a liquid droplet is modified by consideringnon-ideal gas. We simulate high pressure CO2 flows through aLaval nozzle, which was experimentally investigated byLettieri et al. High-pressure CO2 passes through the nozzle,leading to a decrease in its pressure and temperature. It reachesthe supercooled condition near the throat. Nucleation and thesubsequent growth of droplets lead to an increase in thecondensate mass fraction in the diverging area. The proposedmethod for real gas reproduced the peak of pressuredistribution owing to the release of latent heat, whereas thenumerical result assuming ideal gas is different from theexperimental result. The nucleation region obtained using thepresent method is earlier and narrower than that in the case ofideal gas. The early and rapid nucleation leads to the high masscondensate rate at the outlet. These results show thatconsidering the real gas effect and nonequilibriumcondensation is crucial for developing the impeller of acompressor for the supercritical CO2 Brayton cycle.
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U2 - 10.1115/GT2018-75592
DO - 10.1115/GT2018-75592
M3 - Conference contribution
AN - SCOPUS:85053931001
SN - 9780791851180
T3 - Proceedings of the ASME Turbo Expo
BT - Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy
PB - American Society of Mechanical Engineers (ASME)
T2 - ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition, GT 2018
Y2 - 11 June 2018 through 15 June 2018
ER -