Loads analysis and structural optimization of a high aspect ratio, composite wing aircraft

Composite structures have shown a prominent impact in the aircraft structural design. With an increasing shift towards incorporating more composite materials in the primary aircraft structure it is imperative to have corresponding design tools to simplify the design process. In the present work, a simplified implementation for composite optimization has been developed within the DLR-AE (German Aerospace Centre, Institute of Aeroelasticity) automated aeroelastic structural design framework cpacs-MONA. This paper presents the results of structural optimization of a high aspect ratio composite wing aircraft model developed in the DLR project ATLAs. The generation of almost all involved simulation models for this study is done using the in-house DLR tool ModGen. An aeroelastic trim analysis is conducted for various manoeuvre and gust conditions. A load selection process is used to determine the most relevant sizing load cases. A comparison is made between the optimization results of a composite wing and an aluminium wing to demonstrate the more favourable strength to weight ratio of the composite wing. A manoeuvre load alleviation procedure has been introduced in the load calculation process. The results show further weight savings in the design process when load alleviation is utilized due to reduction in the span wise bending moment.

[1]  Volker Gollnick,et al.  Communication in aircraft design : Can we establish a common language? , 2012 .

[2]  Zafer Gürdal,et al.  Stiffness Optimization of Composite Wings with Aeroelastic Constraints , 2013 .

[3]  Raphael T. Haftka,et al.  Preliminary design of composite wings for buckling, strength and displacement constraints , 1979 .

[4]  Roeland De Breuker,et al.  Optimization, Manufacturing and Testing of a Composite Wing with Maximized Tip Deflection , 2016 .

[5]  Markus Ritter,et al.  An Extended Modal Approach for Nonlinear Aeroelastic Simulations of Highly Flexible Aircraft Structures , 2017 .

[6]  Thomas Klimmek,et al.  Loads and Structural Optimization Process for Composite Long Range Transport Aircraft Configuration , 2018, 2018 Multidisciplinary Analysis and Optimization Conference.

[7]  Roeland De Breuker,et al.  Implementation of Active and Passive Load Alleviation Methods on a Generic mid-Range Aircraft Configuration , 2018, 2018 Multidisciplinary Analysis and Optimization Conference.

[8]  Autar Kaw,et al.  Mechanics of Composite Materials , 1997 .

[9]  Christos Kassapoglou,et al.  Design and Analysis of Composite Structures: With Applications to Aerospace Structures , 2010 .

[10]  T. Weisshaar.  Aeroelastic Tailoring of Forward Swept Composite Wings , 1981 .

[11]  Raphael T. Haftka,et al.  Optimization of Flexible Wing Structures Subject to Strength and Induced Drag Constraints , 1977 .

[12]  Samuel T. IJsselmuiden.  Optimal Design of Variable Stiffness Composite Structures using Lamination Parameters , 2011 .

[13]  Thomas Klimmek,et al.  Parametric Set-Up of a Structural Model for FERMAT Configuration for Aeroelastic and Loads Analysis , 2014 .

[14]  T. Klimmek,et al.  CPACS-MONA – AN INDEPENDENT AND IN HIGH-FIDELITY BASED MDO TASKS INTEGRATED PROCESS FOR THE STRUCTURAL AND AEROELASTIC DESIGN OF AIRCRAFT CONFIGURATIONS , 2019 .