Optimal design study of thermoacoustic regenerator with lexicographic optimisation method

Abstract

Thermoacoustic heat engines provide a practical solution to the problem of heat management where heat can be pumped or spot cooling can be produced. However, the most inhibiting characteristic of thermoacoustic cooling is their current lack of efficiencies. This paper illustrates the use of the augmented ε-constraint method implemented in GAMS (General Algebraic Modeling Software), aimed at optimizing the geometry of a thermoacoustic regenerator. Lexicographic optimization is presented as an alternative optimization technique to the common used weighting methods. This approach establishes a hierarchical order among all the optimization objectives instead of giving them a specific (and most of the time, arbitrary) weight. A practical example is given, in a hypothetical scenario, showing how the proposed optimization technique may help thermoacoustic regenerator designers to identify Pareto optimal solutions when dealing with geometric parameters. This study highlights the fact that the geometrical parameters are interdependent, which support the use of a multiobjective approach for optimization in thermoacoustic.