A Natural Convection Application: Optimization of Rib Roughened Chimneys

Abstract

In this chapter a natural convection optimization exercise is presented. The exercise is about heat and mass transfer enhancement in rib roughened chimneys. Following the same scheme of the previous chapter the problem is presented and the set-up of the optimization process discussed focusing on the methodology aspects. A rather large seven-steps approach to optimization is proposed mainly for educational purpose. The optimization process includes: two different full factorial DOEs, one sensitivity analysis on the main parameters characterizing the problem, two RSMs based on the DOE data (namely, Sobol and Gaussian processes), one stochastic optimization using multi-objective genetic algorithm, and one deterministic optimization by means of Nelder and Mead simplex method. The analyses are carried out by means of computational fluid dynamics simulations and the results of the process are presented and discussed from the optimization point of view.

La perfection est réalisée,pas quand il n’y a rien à davantage ajouter,mais quand il n’y a plus rien à emporter.

Perfection is achieved,not when there is nothing more to add,but when there is nothing left to take away.

Antoine de Saint-Exupéry