Impact of Square Fuel Assemblies Arrangement on Fluid Flow and Heat Transfer Enhancement inside Water Filled Enclosures

Abstract

Abstract. Through this paper, the hydrodynamic and thermal characteristics of a Newtonian fluid within a square cold enclosure containing four inner heaters, arranged in different manners, are numerically investigated. To do so, a developed computer code based on the finite volume method and the SIMPLER algorithm is used. The validity of the latter was ascertained after the comparison between the obtained results and the experimental and numerical ones already available in the literature. To make clear the effect of pertinent parameters such the Rayleigh number and the distance between these heaters, the phenomenon was reported by means of Streamlines, Isotherm plots, velocity and temperature profiles, with a special attention to the local and average Nusselt number evolution. As shown in the latter, taking into account the heaters' arrangement into the enclosure leads to a significant improvement of the overall transfer. Consequently, powerful correlations predicting the heat transfer ratio into the cold square as a function of the heaters' disposition are proposed which predict within ±1% the numerical results.

Natural convection between hot and cold cylinders in enclosed space filled with copper-water nanofluid

“…Therefore, several researches have been conducted for studying the free convection heat transfer within these geometries. The challenging point of the seworks is looking for the optimal parameters that improve the heat transfer rate while remaining the fl w more stable [27][28][29]. It was observed that the fl w motions and the heat transfer rate are significantly influenced by the thermo-physical characteristics of a fluid (such as density, thermal conductivity, specifi heat transfer, etc.)…”

Natural-convection of Newtonian fluids between two concentric cylinders of a special cross-sectional form

“…Indeed, many experimental and numerical studies have been accomplished to analyze and determine quantitatively the rate of natural-convection heat transfer between two concentric cylinders [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Mack and Bishop [1] they performed the earlier study of natural-convection between two horizontal concentric cylinders of circular cross-sectional shape.…”

“…Also, the effect of Prandtl number on thermal patterns becomes negligible when Pr > 10. Raghi et al [11] numerically investigated the natural-convection inside an enclosure of square cross-section where there are small cross-sectional squares. The work studied the effects of small square number and their arrangement, Rayleigh number on hydrodynamic and thermal behaviors.…”