## THERMAL SCIENCE

International Scientific Journal

### NANOPARTICLE SHAPE EFFECT ON THE NATURAL-CONVECTION HEAT TRANSFER OF HYBRID NANOFLUID INSIDE A U-SHAPED ENCLOSURE

**ABSTRACT**

The effect of nanoparticle shape on the natural-convection heat transfer of Cu-Al2O3-water hybrid nanofluid inside a U-shaped enclosure is presented in this paper. The governing equations are transformed into the dimensionless form using dimensionless variables. A three-node triangular finite element method is used with the Newton-Raphson method to solve the problem numerically. The streamlines and isotherms as well as the local and average Nusselt numbers are presented for the fluid-flow with Rayleigh number of 104 to 106. It is found that blade nanoparticle shape produces the highest heat transfer rate while sphere is the lowest.

**KEYWORDS**

PAPER SUBMITTED: 2020-08-18

PAPER REVISED: 2020-10-19

PAPER ACCEPTED: 2021-01-09

PUBLISHED ONLINE: 2021-04-10

**THERMAL SCIENCE** YEAR

**2022**, VOLUME

**26**, ISSUE

**Issue 1**, PAGES [463 - 475]

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