AN APPLICATION OF GRADIENT VARIABLE-THRESHOLD TOPOLOGY OPTIMIZATION IN AIRCRAFT STRENGTHENING FRAME DESIGN

In order to reduce the weight of aircraft structures effectively, the skeleton of aircraft is treated in the conceptual design of strengthening frame. By analyzing the concept of 'gradient threshold' and pointing out its weakness, the author proposes the concept of 'modified gradient threshold' and combines it with the strategy of 'constraint compensation' to form a new kind of topology optimization algorithm for structural layout of a strengthening frame. The topology optimization results of several examples show that their layouts are good. We can see that, using the combination of CAD/CAE and topology optimization for aircraft strengthening frame conceptual design is feasible and that the proposed 'modified gradient threshold' topology optimization algorithm is effective.