الفهرس 
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Abstract
A 3D numerical simulation was performed to study the transport phenomena that occur when a swirl air jet is issuing perpendicular to a crossflow of air flowing over a hot flat plate to enhance the cooling process of the hot flat plate. The finite element method with SST k-ω turbulence model was employed for this numerical study after validation with experimental data from the literature. A parametric study was performed by varying Reynolds number, Re_j, dimensionless jet to plate spacings, Z/D, swirl number, SW, and blockage ratios, BR. The thermal performance was assessed by the average heat transfer coefficient, h ̅_j, in addition to the ratio of heat transfer coefficient between the proposed setup involving crossflow with jet to the reference case of crossflow without jet, h ̅_j/h ̅_woj. The performance evaluation coefficient, PEC, was chosen to identify the best possible thermal and hydraulic performance. Results show that for all the studied cases, there is a clear enhancement of the heat transfer rates when employing a combination of swirl jet with crossflow over a flat plate compared to the case of crossflow without jet. The maximum value of PEC was 1.8 occurring at Reynolds number, Re_j, of 10000, swirl number of 0.9, blockage ratio of 0.6, and jet-to-plate spacing of 2D.
Keywords:
Swirl jet impingement
Cooling jet
Heat transfer enhancement
Performance evaluation coefficient (PEC)