Browsing by Author "Almerbati, A"

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    Arrays of flow channels with heat transfer embedded in conducting walls
    (International Journal of Heat and Mass Transfer, 2016-08-01) Bejan, A; Almerbati, A; Lorente, S; Sabau, AS; Klett, JW
    Here we illustrate the free search for the optimal geometry of flow channel cross-sections that meet two objectives simultaneously: reduced resistances to heat transfer and fluid flow. The element cross section and the wall material are fixed, while the shape of the fluid flow opening, or the wetted perimeter is free to vary. Two element cross sections are considered, square and equilateral triangular. We find that the two objectives are best met when the solid wall thickness is uniform, i.e., when the wetted perimeters are square and triangular, respectively. We also consider arrays of square elements and triangular elements, on the basis of equal mass flow rate per unit of array cross sectional area. The conclusion is that the array of triangular elements meets the two objectives better than the array of square elements.
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    Energy design for dense neighborhoods: One heat pump rejects heat, the other absorbs heat from the same loop
    (International Journal of Thermal Sciences, 2015-06-29) Almerbati, A; Lorente, S; Bejan, A
    © 2015 Elsevier Masson SAS. This paper documents the joint performance of heat pumps that are served by a common loop buried in the ground, and which operate simultaneously: one heat pump absorbs heat from the buried loop whereas the other one rejects heat. A background flow is circulated in the underground loop even when the two heat pumps are not operating. The objective is to determine the performance and the manner in which it is affected by the way in which the two heat pumps are connected to the loop. The performance measures are the heat transfer rates into and out of the heat pumps, and the total pumping power required by the assembly. The paper documents the individual performance of the heat pumps, and their relative performance, which is the ratio of heating absorbed by one pump to the heating rejected by the other pump.