Thermal Resistance Minimization of a Fin-and-Porous-Medium Heat Sink with Evolutionary Algorithms

Abstract

This article presents a conceptual design of a heat sink combining a porous medium whose matrix is highly conductive and a fin. A simplified model is presented to estimate the performance of the system, relying on Darcy law and local thermal equilibrium. The objective is to minimize the hot-spot temperature under global mass constraint by using an optimization procedure based on genetic algorithms. The design variables are the porosity and material of each layer of the porous medium, the fin material, height, and width, the aspect ratio of the heat sink, and the shape of a weightless upper corner deflector which reduces the width of the inlet and outlet air slots while removing the less useful mass. Results show that the optimal porous layers were generally of copper, independent of the mass constraint. However, the fin is mostly beneficial for heavier designs, while the deflector becomes more important when lightness is required. These two special features show their efficiency by allowing a mass reduction of 95% with a decrease of only 24% in the cooling performance.

Thermal shielding of multilayer walls with phase change materials under different transient boundary conditions

“…GAs are optimization tools relying on Darwinian evolution principles, and have been used successfully for the design of several heat transfer and energy systems. In particular, they have been able to determine optimal materials in many systems, e.g., [18][19][20][21]. We will not explain here the details of this algorithm that is becoming more and more common in the domain.…”

Conceptual optimization of a rotary heat exchanger with a porous core

“…In the previous sections, a simplified model with local thermal equilibrium between the fluid and the solid matrix has been assumed [20,22]. A two-temperature model including conduction will now be used to investigate the effect of non-local thermal equilibrium on bothL opt andq 00 for the two same porous structure geometries [21].…”

“…1. Next, assuming that the solid and fluid composing the porous structure are in local thermal equilibrium and neglecting conduction heat transfer within the porous structure (these assumptions will be relaxed later) [20][21][22], the conservation of energy states that…”

Nonlocal Modeling and Swarm-Based Design of Heat Sinks

“…Further, others have coupled porous media models with GAs to optimize heat sink designs [9][10][11].…”

“…In every iteration, each particle is updated by its attraction to its own best position id p , and that of its neighbors nd p , through Equations (9) and (10). When a given criterion is satisfied, the iteration exits with what is taken to be the optimal solution.…”