Numerical simulation of laminar flow and heat transfer over banks of staggered cylinders

Abstract

SUMMARYA study is conducted to investigate forced convective ow and heat transfer over a bank of staggered cylinders. Using a novel numerical formulation based on a non-orthogonal collocated grid in a physical plane, the e ects of Reynolds number and cylinder spacing on the ow and heat transfer behaviour are systematically studied. It is observed that both the Reynolds number and cylinder spacing in uence the recirculatory vortex formation and growth in the region between the cylinders; in turn, the rates of heat transfer between the uid and the staggered cylinders are a ected. As the cylinder spacing decreases, the size and length of eddies reduce. For su ciently small spacings, eddy formation is completely suppressed even at high Reynolds number. Pressure drop and Nusselt number predictions based on numerical study are in excellent agreement with available correlations. The study provides useful insight on the detailed ow and heat transfer phenomena for the case of a bank of staggered cylinders.

The effect of Al 2 O 3 -water nanofluid on the heat transfer and entropy generation of laminar forced convection through isotropic porous media

“…Examination of the two arrangements using e ¼ 0:84 and e ¼ 0:91 revealed that the velocity gradients increase when the porosity decreases, which agrees with the information presented previously in Ref. [44]. For the sake of brevity, contours for the staggered and in-line arrangements using e ¼ 0:91 are not illustrated.…”

Pressure drop of laminar gas flows in a microchannel containing various pillar matrices

“…et al [16]. Experiments preformed by Kosar et al [11] on micro circular pillar structures have no good agreement with that of conventional macro correlations.…”

Numerical study of heat transfer over banks of rods in small Reynolds number cross-flow

“…The role of finite Reynolds number flow and the deviation due to non-linearities from the original Darcy's law have been extensively discussed in the literature. There are much less numerical works on heat transfer over banks of rods in low Reynolds number cross-flow [11][12][13][14][15][16]. In the context of porous media, one of the issues is that of local thermal equilibrium of the fluid and the solid matrix constituting the porous medium.…”

“…This problem is much more complex than the isothermal one, since heat transfer not only depends on the porosity and the Reynolds number, but also on the Prandtl number and on the thermal conditions on the solid surfaces. The range of parameters and boundary conditions found in [11][12][13][14][15][16] are shown in Table 1.…”