Optimal sizing of large engineering systems by separable duals

In the preliminary optimal sizing of large engineering systems very simplified system models are often used. The paper deals with one class of problems which is composed of separable functions. It examines the type of system which results in sizing problems of this form and demonstrates that a particular form of the problem appears to have a general applicability. The engineering literature contains no mention of the dual form of this problem which is derived here and which has attractive properties from the point of view of developing rapid solution algorithms for practical design purposes.