## THERMAL SCIENCE

International Scientific Journal

### CONVECTIVE HEAT TRANSFER OVER A WALL MOUNTED CUBE AT DIFFERENT ANGLE OF ATTACK USING LARGE EDDY SIMULATION

**ABSTRACT**

Turbulent fluid flow and convective heat transfer over the wall mounted cube in different flow angle of attack have been studied numerically using Large Eddy Simulation. Cube faces and plate have a constant heat flux. Dynamic Smagorinsky (DS) subgrid scale model were used in this study. Angles were in the range 0≤θ≤45 and Reynolds number based on the cube height and free stream velocity was 4200. The numerical simulation results were compared with the experimental data of Nakamura et al [6, 7]. Characteristics of fluid flow field and heat transfer compared for four angles of attack. Flow around the cube was classified to four regimes. Results was represented in the form of time averaged normalized streamwise velocity and Reynolds stress in different positions, temperature contours, local and average Nusselt number over the faces of cube. Local convective heat transfer on cube faces was affected by flow pattern around the cube. The local convective heat transfer from the faces of the cube and plate are directly related to the complex phenomena such as horse shoe vortex, arch vortexes in behind the cube, separation and reattachment. Results show that overall convective heat transfer of cube and mean drag coefficient have maximum and minimum value at θ=0 deg and θ=25 deg respectively.

**KEYWORDS**

PAPER SUBMITTED: 2011-06-14

PAPER REVISED: 2013-02-20

PAPER ACCEPTED: 2013-06-26

PUBLISHED ONLINE: 2013-07-06

**THERMAL SCIENCE** YEAR

**2014**, VOLUME

**18**, ISSUE

**Supplement 2**, PAGES [S301 - S315]

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