HIERARCHICAL SELECTION DECISION SUPPORT PROBLEMS IN CONCEPTUAL DESIGN

Abstract

In this paper, the application of the coupled Decision Support Problem (DSP) formulation to hierarchical selection in engineering design is presented. Selection involves making a choice among a number of alternatives taking into account several attributes. The term hierarchical selection refers to selection problems that share a number of coupling attributes among them. If the various selection problems are solved independently without taking the interaction among them into consideration, it is not likely that an overall superior design will be achieved. The uniqueness of the present approach lies on the simultaneous solution of various selection problems by reformulating them as a single compromise DSP. The resulting compromise DSP can be solved using any LP code that has the capability of handling variable coefficients. The approach is illustrated by means of an example involving the hierarchical selection of a heat exchanger concept and a cooling fluid for a specific application. The example, though simplified, is representative of the complexities inherent in “catalog design” a procedure in which a system is assembled by selecting standard components from catalogs of available components. The emphasis in this paper, however, is placed on explaining the method and not on the size or the comprehensive nature of the example problem.