PrandtlPlane wing-box least-weight design: A multi-scale optimisation approach

Abstract

The PrandtlPlane (PrP) aircraft wing-box least-weight design is presented in this work. This design problem is formulated as a constrained non-linear programming problem (CNLPP), by integrating static, buckling, fatigue and manufacturability requirements, under different loading conditions. The solution search is carried out by means of a suitable multi-scale optimisation (MSO) approach. The physical responses involved into the CNLPP formulation are evaluated at the wing-box architecture level (macroscopic scale) and at the stiffened panel level (component scale), as well. The scale transition is ensured by means of a suitable global-local (GL) modelling approach, while the CNLPP is solved by means of an in-house genetic algorithm. The effectiveness of the proposed approach is tested on the PrP wing-box structure, but the presented strategy can be easily extended to conventional aircraft wings.

A DoE-based approach for the implementation of structural surrogate models in the early stage design of box-wing aircraft

“…Focusing on structural sizing of front and rear wings, the structural parameters of vertical wings and vertical tail plane are fixed to values obtained in [32] and more detailed in [33]; although the number of structural parameters has been reduced to that of the horizontal wings this is still high for the generation of a DoE, regardless of the design to be considered (e.g. twolevel full factorial, or a central composite faced design, or three-level partial factorial, and so on), requiring a very high number of FEM simulations.…”

“…• according to [32] and [33], the skin thickness ratio for the front wing seems to have a little influence on structural design, therefore it has been fixed to the value of 0.295 as done in these works;…”

“…Aerospace Science and Technology (2021) doi: 10.1016/j.ast.2021.106968 15 front and rear wings. To this end, the structural design variables have been varied within ranges shown in Table 5; the choice of such ranges of variation has been made on the basis of previous results reported in [32].…”

Structural analysis and improvement for a new form traveler in long-span cantilever-casting arch bridge

“…The C-type hook consists of a box-shaped section of the welded steel plate, and during the concrete casting of the arch box, the dead weight of the form traveler and the wet weight of the concrete is assumed by the anchor suspender. [24][25][26][27][28][29][30][31][32] The main performance parameters of the new form traveler are shown in Table 1.…”

“…Structural optimization includes performance improvement and weight reduction, which is particularly important in aircraft structure. [23][24][25][26][27][28] This paper, based on the new form traveler adopted in the cantilever construction of Ye-Lang Lake Bridge with a main span of 210 m, aims to improve its structural details and verifies its working performance by carrying out the load test, thus provides useful references for the cantilever casting of similar long-span arch bridges in the future.…”