Open Access
ARTICLE
A COMPARISON OF THE EQUILIBRIUM AND THE DROPLETS BASED NON-EQUILIBRIUM COMPRESSIBLE PHASE CHANGE SOLVERS FOR CONDENSATION OF CARBON DIOXIDE INSIDE NOZZLES
Kapil Dev Choudhary, Shyam Sunder Yadav†
, Mani Sankar Dasgupta
Birla Institute of Technology and Science, Pilani, Rajasthan, 333031, India
† Corresponding author. Email: ss.yadav@pilani.bits-pilani.ac.in
Frontiers in Heat and Mass Transfer 2021, 16, 1-10. https://doi.org/10.5098/hmt.16.14
Abstract
In the current work, we simulate the condensation of supercritical CO
2 during its high speed flow inside two different converging-diverging nozzles. We use the homogeneous equilibrium method and the classical nucleation theory based non-equilibrium phase change model for this purpose.
The simulation results indicate significant influence of the nozzle inlet condition, nozzle shape and the fluid thermophysical behaviour on the nonequilibrium conditions prevailing inside the nozzles. We observe very low, ∼0.15 K, supercooling for the flow of CO
2 inside the Claudio Lettieri
nozzle compared to the supercooling of ∼3 K observed for the Berana nozzle. Very high nucleation rate (∼ 10
35 nucleation per m
3
per second) is
observed before the throat of the nozzles which remains confined to a very small axial distance. The nucleation rate takes much smaller values (∼ 10
7
nucleation per m
3
per second) in rest of the nozzle. A maximum of 70 nano meter sized droplets with number densities of the order of 10
21 droplets
per m
3
are predicted inside the nozzles. Liquid mass fraction values between 0.2 to 0.4 are predicted by the solvers inside the nozzles. These results
will be useful to the engineering community involved in the design and fabrication of CO
2 based systems.
Keywords
Cite This Article
Choudhary, K. D., Yadav, S. S. (2021). A COMPARISON OF THE EQUILIBRIUM AND THE DROPLETS BASED NON-EQUILIBRIUM COMPRESSIBLE PHASE CHANGE SOLVERS FOR CONDENSATION OF CARBON DIOXIDE INSIDE NOZZLES.
Frontiers in Heat and Mass Transfer, 16(1), 1–10. https://doi.org/10.5098/hmt.16.14