(262y) Mathematical Modeling of Compressed CO2 Expansion through a Coanda Nozzle
AIChE Annual Meeting
2016
2016 AIChE Annual Meeting
Engineering Sciences and Fundamentals
Poster Session: Thermodynamics and Transport Properties (Area 1A)
Monday, November 14, 2016 - 6:00pm to 8:00pm
A Coanda nozzle can be used to produce a high velocity mixture of air, gaseous CO2, and dry ice particles from a supply of liquid CO2. Such a process is effective (for instance) for residue-free rapid cooling or precision cleaning. A thermodynamic and computational fluid dynamics (CFD) analysis of this flow is presented for the purpose of optimizing the process parameters, which include the temperature of the liquid CO2supply, the flow rate, and the pressure and nozzle and air configuration.
Temperature, pressure, velocity and mass fraction profile distributions have been modeled on the spray-nozzle system. Flow characteristics have been quantified for dry ice particle sizes of 1.0x10-3m, 1.0x10-4m and 1.0x10-5m. Maximum velocity and residence time as a function of inlet temperature have been simulated and quantified. The analysis suggests that as inlet CO2temperature increases, the maximum velocity increases and the particle residence time decreases. Decreasing dry ice particle size decreases the residence time in the nozzle channel. Overall, this study provides a basis for optimizing the temperature and velocity profiles, and thus the cooling or cleaning capacity of such Coanda devices.