## THERMAL SCIENCE

International Scientific Journal

### COMPUTATION OF HEAT TRANSFER OF A PLANE TURBULENT JET IMPINGING A MOVING PLATE

**ABSTRACT**

This study examines the performance of one point closure turbulence models in predicting of heat and momentum transfer of impinging flows. The scope of this paper is limited to impinging jet on a moving wall and heat transfer. The impinging distance is fixed to 8 thickness of the nozzle (8e) for this study. Two parameters are considered: the jet exit Reynolds number (10000≤Re≤25000) and the jet-surface velocity ratio (0≤Rsj≤4). the flow field structure at a given surface-to-jet velocity ratio is independent of the jet Reynolds number, a slight modification of the flow field is observed for low surface-to-jet velocity ratio (Rsj<0.25) whereas at higher ratios Rsj>0.25, the flow field is significantly modified. Good agreement with experimental results is obtained for surface-to-jet velocity ratio 0≤Rsj≤2. the purpose of this paper is to consider the case of higher of surface-to-jet velocity Rsj>2. A further study of heat transfer is achieved and shows that the stagnation points the local heat transfer coefficient have a maximum value. The local Nusselt number at the impinging region tends to decrease significantly when Rsj≤1.5. The evolution of average Nusselt number is correlated according to the surface-to-jet velocity ratios for each Reynolds number.

**KEYWORDS**

PAPER SUBMITTED: 2011-10-27

PAPER REVISED: 2012-06-15

PAPER ACCEPTED: 2012-06-15

**THERMAL SCIENCE** YEAR

**2014**, VOLUME

**18**, ISSUE

**4**, PAGES [1259 - 1271]

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