MIXED CONVECTION OF FUNCTIONALIZED DWCNT/WATER NANOFLUID IN BAFFLED LID-DRIVEN CAVITIES

AuthorsMohammad Hemmat Esfe, Ali Akbar Abbasian Arani, YAN Wei-Mon, Alireza Aghaie, Masoud Afrand, Nima Sina
JournalTHERM SCI
Volume number22
Paper TypeFull Paper
Published At2018
Journal GradeISI
Journal TypeElectronic
Journal CountryIran, Islamic Republic Of

Abstract

The present study aims to evaluate the mixed convection flow and heat transfer of functionalized DWCNT/Water nanofluids with variable properties in a cavity having hot baffles. The investigation is performed at different nanoparticles volume fraction including 0, 0.0002, 0.001, 0.002, and 0.004, Richardson numbers ranging from 0.01 to 100, inclination angles ranging from 0 to 60° and at constant Grashof number of 10 4 . The results presented as streamlines and isotherms plot and Nusselt number diagrams. According to the finding with increasing nanoparticles volume fraction and distance between the left hot baffles of nanoparticles average Nusselt number enhances for all considered Richardson numbers and cavity inclination angles. Also with increasing Richardson number, the rate of changes of average Nusselt number increase with increasing distance between the left hot baffles. For example, at Richardson number of 0.01, by increasing L1 from 0.4 to 0.6, the average Nusselt number increases 7%; while for similar situation at Richardson number of 0.1, 1.0 and 10, the average Nusselt number increases respectively 17%, 24% and 26%. At all Richardson numbers, the maximum value of average Nusselt number is achieved for a minimum length of left baffles.