Investigation of optimal position of a vortex generator in a blocked channel for heat transfer enhancement of electronic chips

Abstract A heat transfer optimization of a channel including three blocks attached to its bottom wall (i.e. electronic chips) with an inserted triangular bar acting as a vortex generator (control element) is carried out in order to maximize heat transfer rate as well as to achieve heat flux uniformity over the blocks. Genetic algorithm (GA) combined with Gaussian Process (GP) is utilized as the optimization algorithm. The Nusselt number of the samples is computed with the aid of a Navier–Stokes solver. It is shown that a well trained GP can accurately predict the Nusselt number of each block separately which matches very well with data obtained from the outputs of Navier–Stokes solver. The fitness function is defined as the summation of weighted Nusselt numbers and standard deviation term multiplied by a constant coefficient (to control the priority of homogeneity). The optimization results show that the greater value of the standard deviation multiplier, the more uniform Nusselt numbers. In addition, the optimum location of vortex generator is seen to be above the first block for which uniformity is neglected; however, it displaces from top of the first block to the top of the second block as uniformity become more important. Another conclusion obtained in the present work is that the optimal position of the vortex generator is independent of the Reynolds number.

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