Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
Numerical Study of a Cavity With and Without Radiation Including a Participating Wet Air
Submission Author:
Ana Carolina Oliveira de Paula , SP
Co-Authors:
Ana Carolina Oliveira de Paula, Kamal Ismail
Presenter: Ana Carolina Oliveira de Paula
doi://10.26678/ABCM.ENCIT2018.CIT18-0027
Abstract
The present paper numerically investigates heat transfer and fluid flow by binary natural convection and radiative heat transfer in an inclined solar still cavity filled with air and water vapor. A comparison is performed for a cavity where thermal radiation is included and one where it is not. For the radiative cavity, walls are considered surfaces that reflect and emit diffusively, while wet air is considered to be a participating medium. For the non-radiative cavity, radiative exchange at the walls and working fluid is not considered. Water vapor is at the saturation state. Conservative equations (mass, momentum, energy and species) are analyzed and discretized through control volume method (CVM). Velocity-pressure linkage is solved through the SIMPLE algorithm. Radiative transfer is solved using the discrete ordinates method (DOM) and is coupled in the energy equation. Velocity, temperature and concentration fields are obtained for a Rayleigh number range where laminar flow prevails. Results show that radiation heat transfer changes fluid dynamics inside the solar still cavity. Temperature and velocity contour lines tend to concentrate close to the wall of higher emissivity. Changes were also present in Nusselt number profiles, where peaks were observed in the regions close to the walls.
Keywords
solar still, binary natural convection, radiative transfer, discrete ordinates method
