Development and Application of a Flexibility-Based Method for Multi-Scale Design

Abstract

A flexibility-based approach is presented for the solution of multiscale engineering design problems. The methodology is aimed at enhancing distribution of design activities and reducing the number of costly iterations between multiple engineering teams operating on different scales. This goal is achieved by exchanging flexible families of solutions rather than single point solutions, thereby reducing the need for iteration between scales. The effectiveness of the approach is illustrated by a two-level problem involving the system-level design of a gas turbine engine and the mesoscale design of cellular material for the combustor liner. A multi-objective design problem formulation is used to obtain families of prismatic cellular materials that embody a range of tradeoffs between conflicting thermal and structural performance objectives. The results are communicated to the system level and a solution is chosen to meet system-level goals as closely as possible. The effectiveness of the method is evaluated by comparison with a benchmark integrated design method. The approach facilitates identification of satisfactory or nearly optimal solutions quickly and with minimal iterations between scales.