Fluid flow and heat transfer of natural convection induced around a vertical row of heated horizontal cylinders

Numerical investigation of the laminar natural convection heat transfer from two horizontally attached horizontal cylinders

“…It differs from those previous studies [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] that are restricted to the arrays of cylinders in free space, where the optimal spacing in the arrays must take the volumetric heat transfer into account, rather than simply maximize the value of Nusselt number for the upper cylinders or the whole arrays. Bejan et al [42] proposed a metric for measuring the heat transfer volumetric density to optimize the spacing of a staggered tube bank with the centers of any three consecutive cylinders forming equilateral triangles in a fixed volume.…”

“…Analogous phenomena have been reported in molten salts in a successive paper by Yuanwei Lu et al [40], who investigated the natural convection from the vertical arrays of 2-8 horizontal cylinders for the Rayleigh number in the range between 2 Â 10 3 and 5 Â 10 5 and the separation distances increasing from 2 to 9 times cylinder diameter. More recently, Kitamura et al [41] have conducted an experimental analysis on the natural convection heat transfer and flow from a single vertical row of heated horizontal cylinders consisting of ten cylinders in air, with the purpose of deriving the heat transfer correlating equations for any individual cylinder in the array, in particular, also presenting the correlation for the turbulent flows. Besides, the effect of the temperature imbalance ratio (define as DT L =DT U ) on natural convection heat transfer from the upper cylinder in a vertical array consisting of a pair of cylinders has been investigated experimentally and numerically by Sparrow and Niethammer [24], and Park and Chang [26], via considering the temperature imbalance ratio to be one and two, respectively.…”

Mesoscopic approach for steady‐state free convection in a diamond array

“…Consequently, rooted from the gas kinetics, LBM is considered as a persuasive numerical technique tool in casting hydrodynamics in fluid flows in various engineering fields . Recently, it has been extended to simulate free convection in a considerable variety of complex dynamic and thermal behaviors, relayed on the temperature difference between the inner and outer bodies, the sizes and shapes of the inner bodies, their arrangement and their position . The most prominent model, lattice Bhatnagar‐Gross‐Krook (BGK) is used in this paper, which approximates the collision operator as a relaxation of the distribution function towards a local equilibrium distribution .…”

“…These studies were motivated by the desire to understand the fundamental physics and free convection characterization inside the cavity that can be influenced and affected by the sizes and shapes of the interior bodies, their number, position, arrangement, and also the configuration of the cavity . So, due to its substantial significance, heat transfer with free convection in presence of heating cylinders is investigated by many researchers .…”

Maximization of heat transfer density from a vertical array of flat tubes in cross flow under fixed pressure drop using constructal design

“…At an intermediate Reynolds number, the results showed that the Nusselt number of disorderly distribution was less than from that of the orderly distribution. Natural convection from a vertical array of circular cylinders can be found in Corcione and Kitamura et al Forced convection from a series of different shaped cylinders placed in a channel was studied by Bahaidarah et al In this study, a series of circular, oval, diamond, and flat cylinders were placed in a channel. The range of Reynolds number was 25 ≤ Re ≤ 350.…”