Constructal optimisation of conjugate triangular cooling channels with internal heat generation

Abstract

This paper presents the development of the three-dimensional flow architecture of conjugate cooling channels in forced convection with internal heat generation within a solid.Two types of cross-section channel geometries were used. The first involved equilateral triangles with three equal legs in length and all three internal angles of 60 0 . The second was isosceles right triangles with two legs of equal length and internal angles of 90 0 , 45 0 and 45 0 .Both the equilateral triangle and isosceles right triangle are special case of triangle that can easily and uniformly be packed and arranged to form a larger constructs. The configurationswere optimised in such a way that the peak temperature of the heat generating solid was minimised subject to the constraint of a fixed global volume of the solid material. The cooling fluid was driven through the channels by the pressure difference across the channel. The degrees of freedom of the channels were aspect ratio, hydraulic diameter and channel to channel spacing ratio. The shape of the channel was allowed to morph to determine the best configuration that gives the lowest thermal resistance. A gradient-based optimisation algorithm was applied in order to search for the best optimal geometric configurations that improve thermal performance by minimising thermal resistance for a wide range of dimensionless pressure difference. The effect of porosities, applied pressure and heat generation rate on the optimal aspect ratio and channel to channel spacing are reported. It was found that there are unique optimal design variables for a given pressure difference.

Constructal heat transfer and fluid flow enhancement optimization for cylindrical microcooling channels with variable cross‐section

“…This current research is an extension of past works [38][39][40] on the application of this theory, where it was shown that the minimized peak temperature was influenced by geometric configurations. The present configuration is considered based on our desire to find the effect of variable cross-section on minimized peak temperature.…”

Constructal branched micromixers with enhanced mixing efficiency: Slender design, sphere mixing chamber and obstacles

“…Many researchers have showed that it is valid for both animate [21][22][23][24][25][26][27][28][29][30][31] and inanimate [30][31][32][33][34]. Furthermore, Constructal law also plays a significant role in the design optimization of engineering systems (see, for example, [35][36][37][38][39][40][41][42][43][44]). In this work, we address the design of micromixer based on the Constructal law.…”