Combining analysis of different performances through the use of dimensional analysis

This article demonstrates that it is possible and valuable to develop a generic evaluation approach for preliminary design based on dimensional analysis and a method for multiple evaluations of heterogeneous performances. The use of dimensional analysis theory allows building a minimal number of aggregate indicators based on the adequate combination of elementary performance variables of the same type. The proposed method is particularly convenient during the preliminary design stage. The reason for using dimensional analysis for early design purpose is that it is strongly based on concepts of similarity and analogy and that analogical reasoning has been proved to play a central role in design contexts. Mathematically, similarity refers to a transformation of variables that leads to a reduction in the number of independent variables that specify a problem. In addition, we argue that dimensional analysis can be integrated in the existing theoretical framework of design (i.e. General Design Theory). We have applied the approach to a case study of the design of a workplace by taking into consideration, for simplification purposes of this article, only two requirements: improving the visual comfort of the occupants and reducing the energy consumption level. This approach may be used in many design contexts in providing a fruitful framework to structure performances and evaluation stage.