## THERMAL SCIENCE

International Scientific Journal

### Thermal Science - Online First

online first only
### Numerical investigation of laminar forced convection heat transfer in rectangular channels with different block geometries using nano-fluids

**ABSTRACT**

This research investigates the laminar steady forced convection heat transfer of a copper-water nano-fluid in a two-dimensional horizontal channel with different block geometries attached to the bottom wall. The block geometries assumed in this research are triangular and curve blocks. The governing equations associated with the required boundary conditions are solved using finite volume method based on the SIMPLE technique and the effects of Reynolds number, nano-fluid volume fraction, block geometry and the numbers of blocks on the local and average Nusselt numbers are explored. The obtained results show that nano-particles can effectively enhance the heat transfer in a channel. Furthermore, the local and average Nusselt number distribution is strongly dependent on the block geometry. As observed, the heat transfer augments with the increase in the Reynolds number and nano-fluid volume fraction for both block geometries. It is also concluded that the average Nusselt number of the curve block is higher than that of the triangular block for different Reynolds numbers which declares the importance of the block geometry in the heat transfer enhancement.

**KEYWORDS**

PAPER SUBMITTED: 2015-01-31

PAPER REVISED: 2015-06-08

PAPER ACCEPTED: 2015-06-30

PUBLISHED ONLINE: 2015-07-03

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