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This work presents a numerical study on the geometric evaluation of forced convective flows over four staggered arrangement of four cylinders. The forced convective flow is considered incompressible, two-dimensional, laminar and unsteady. Geometry varies according to Constructal Design method. The objectives are the maximization of Nusselt number (Nu D ) and minimization of drag coefficient (C D ) between the cylinders and the surrounding flow. Simulations were performed considering Reynolds numbers of Re D = 10, 40 and 150 and air as working fluid, i.e., Prandtl number is assumed Pr = 0.71. The problem presents three degrees of freedom: S T /D (ratio between transversal pitch of the intermediate cylinders and the cylinders diameter), S L1 /D (ratio between the frontal and intermediate cylinders longitudinal pitch and the cylinders diameter) and S L2 /D (ratio between the intermediate and posterior cylinders longitudinal pitch and the cylinders diameter). However, S L1 /D and S L2 /D measures were kept fixed at 1.5 and S T /D varies in the range 1.5 ≤ S T /D ≤ 5.0. The conservation equations of mass, momentum and energy conservation are solved with the Finite Volume Method (FVM). Optimal results for fluid-dynamic study in all Re D cases occurred for the lowest values of S T /D, i.e., (S T /D) o,f = 1.5. For thermal analysis, Nu D behavior was assessed, where optimal results for Re D = 10 and 40 occurred for the highest values of S T /D, whilst, for Re D = 150, the optimal value was achieved for the intermediate ratio of S T /D = 4.0. |
