Entropy Generation Calculation for Turbulent Fully Developed Forced Flow and Heat Transfer of Nanofluids inside Annuli

This paper analytically investigates the entropy generation of AL2O3-water nanofluid flow through annuli with uniform heat flux at the inner wall while the outer wall is insulated. The present study has been done for fully developed and turbulent flow condition and single phase approach is used for the nanofluid modeling and the thermophysical properties of the nanofluid are calculated using available correlations. Control volume approach is selected for calculation of the entropy generation. Total entropy generation is calculated for different values of nanoparticles volume fractions at different geometrical ratios and compared with those of the base fluid. The results for the dependency of entropy generation of the nanofluid on geometrical factors such as L ⁄Dh and D0/Di⁄ are obtained and compared for different nanoparticles volume fractions. For all of mentioned cases, It has been found that that the irreversibility due to fluid flow (pressure drop) is dominant and adding nanoparticles leads to increased entropy generation.

کلیدواژه ها:

Nanofluid ، Entropy generation ، Turbulent forced convection ، Annulus ، Analytical solution