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Computational efficiency is always the major concern in aircraft design. The purpose of this research is to investigate an efficient jig-shape optimization design method. A new jig-shape optimization method is presented in the current study and its application on the high aspect ratio wing is discussed.

First, the effects of bending and torsion on aerodynamic distribution were discussed. The effect of bending deformation was equivalent to the change of attack angle through a new equivalent method. The equivalent attack angle showed a linear dependence on the quadratic function of bending. Then, a new jig-shape optimization method taking integrated structural deformation into account was proposed. The method was realized by four substeps: object decomposition, optimization design, inversion and evaluation.

After the new jig-shape optimization design, both aerodynamic distribution and structural configuration have satisfactory results. Meanwhile, the method takes both bending and torsion deformation into account.

The new jig-shape optimization method can be well used for the high aspect ratio wing.

The new method is an innovation based on the traditional single parameter design method. It is suitable for engineering application.

To propose an integrated algorithm for aerodynamic shape optimization of aircraft wings under the effect of aeroelastic deformations at supersonic regime.

A methodology is proposed in which a high‐fidelity aeroelastic analyser and an aerodynamic optimizer are loosely coupled. The shape optimizer is based on a “CAD‐free” approach and an exact gradient method with a single adjoint state. The global iterative process yields optimal shapes in the at‐rest condition (i.e. with the aeroelastic deformations substracted).

The methodology was tested under different conditions, taking into account a combined optimization goal: to reduce the sonic boom production, while preserving the aerodynamic performances of flexible wings. The objective function model contains both aerodynamic parameters and an acoustic term based on the sonic boom downwards emission.

This paper proposes a shape optimization methodology developed by researchers but aiming at the final strategic goal of creating tools that can be really integrated in design processes.

The paper presents an original loosely coupled method for the shape optimization of flexible wings in which recent and modern techniques are used at different levels of the global algorithm: the aerodynamic optimizer, the aeroelastic analyser, the shape parametrization and the objective function model.

To obtain a good start configuration in the early design phase, simulation tools are used to create a large number of product designs and to evaluate their performance. To reduce the effort for the model generation, analysis and evaluation, a design environment for thin-walled lightweight structures (DELiS) with the focus on structural mechanics of aircrafts has been developed.

The core of DELiS is a parametric model generator, which creates models of thin-walled lightweight structures for the aircraft preliminary design process. It is based on the common parametric aircraft configuration schema (CPACS), which is an abstract aircraft namespace. DELiS facilitates interfaces to several commercial and non-commercial finite element solvers and sizing tools.

The key principles and the advantages of the DELiS process are illustrated. Also, a convergence study of the finite element model of the wing and the fuselage and the result on the mass after the sizing process are shown. Due to the high flexibility of model generation with different levels of detail and the interface to the exchange database CPACS, DELiS is well suited to study the structural behaviour of different aircraft configurations in a multi-disciplinary design process.

The abstract definition of the object-oriented model allows several dimensions of variability, such as different fidelity levels, for the resulting structural model. Wings and fuselages can be interpreted as finite beam models, to calculate the global dynamic behaviour of a structure, or as finite shell models.

This paper aims to present a computational aeroelastic capability based on a fluid–structure interaction (FSI) methodology and validate it using the NASA Common Research Model (CRM). Focus is placed on the effect of the wind tunnel model structural features on the static aeroelastic deformations.

The FSI methodology couples high-fidelity computational fluid dynamics to a simplified beam representation of the finite element model. Beam models of the detailed CRM wind tunnel model and a simplified CRM model are generated. The correlation between the numerical simulations and wind tunnel data for varying angles of attack is analysed and the influence of the model structure on the static aeroelastic deformation and aerodynamics is studied.

The FSI results follow closely the general trend of the experimental data, showing the importance of considering structural model deformations in the aerodynamic simulations. A thorough examination of the results reveals that it is not unequivocal that the fine details of the structural model are important in the aeroelastic predictions.

The influence of some changes in structural deformation on transonic wing aerodynamics appears to be complex and non-linear in nature and should be subject to further investigations.

It is shown that the use of a beam model in the FSI approach provides a reliable alternative to the more costly coupling with the full FE model. It also highlights the non-necessity to develop precise, detailed structural models for accurate FSI simulations.

The purpose of this research is to explore innovative aircraft concepts that use flexible wings and distributed propulsion to significantly reduce fuel burn of future transport aircraft by exploiting multidisciplinary interactions.

Multidisciplinary analysis and trajectory optimization are used to evaluate the mission performance benefits of flexible wing distributed propulsion aircraft concepts.

The flexible wing distributed propulsion aircraft concept was shown to achieve a 4 per cent improvement in L/D over a mission profile consisting of a minimum fuel climb, minimum fuel cruise and continuous descent.

The technologies being investigated may lead to mission adaptive aircraft that can minimize drag, and thus fuel burn, throughout the flight envelope.

The aircraft concepts being explored seek to create synergistic interactions between disciplines for reducing fuel burn while capitalizing on the potential benefits of lightweight, flexible wing structures and distributed propulsion.