Entropy-based optimization of helical fins for heat transfer enhancement inside tubes

The design optimization of a tube with internal helical fins is considered from an entropy generation point of view. The primary focus of the article is to study the optimization results based on entropy-based formulations. Specifically, this work compares the optimal design solution obtained through the minimization of total entropy and through the multiobjective optimization of the heat transfer and frictional entropies when considered as two separate objectives. The latter quantities being associated with heat transfer and pressure drops, it is shown that, from a design optimization point of view, it is important to separate both entropies which are conflicting objectives.