Engine Pylon Topology Optimization Framework Based on Performance and Stress Criteria

Reducing fuel consumption is a major driver for the design of future aircraft. The engine integration primary structure plays a significant role in the integrated engine thrust-specific fuel consumption. A topology optimization framework was developed to design the primary structure integrating the engine to the aircraft wing considering mass, stress, and engine performance criteria. The proposed approach had to address several challenges associated with the use of nonuniform meshes, the integration of the engine model as a super-element, and the presence of nonconforming mesh interfaces. Analytical adjoint evaluations for all the responses were also derived. The framework was tested on a simplified engine model providing a consistent solution

Generalized Geometry Projection: A Unified Approach for Geometric Feature Based Topology Optimization

Structural topology optimization has seen many methodological advances in the past few decades. In this work we focus on continuum-based structural topology optimization and more specifically on geomet- ric feature based approaches, also known as explicit topology optimization, in which a design is described as the assembly of simple geometric components that can change position, size and orientation in the con- sidered design space. We first review various recent de- velopments in explicit topology optimization. We then describe in details three of the reviewed frameworks, which are the Geometry Projection method, the Moving Morphable Components with Esartz material metho

A Multiaxial Stress-Based Critical Distance Methodology To Estimate Fretting Fatigue Life

This work presents a methodology for fretting fatigue life estimation based on the evaluation of a multiaxial fatigue parameter at a critical distance below the contact surface. The fatigue parameter is defined using the Modified Wöhler Curve Method together with a measure of shear stress amplitude based on the Maximum Rectangular Hull concept. To apply the approach in the medium-cycle fatigue regime, the critical distance is assumed to depend on the fatigue life. Available fretting fatigue experiments conducted on a cylinder-on-flat contact configuration made of Al-4%Cu alloy were used to evaluate the methodology. Most of the fatigue life estimates were within factor-of-two boundaries

Aperçus sur la mentalité monastique en Provence au XIe siècle

Amargier Paul. Aperçus sur la mentalité monastique en Provence au XIe siècle. In: Annales. Économies, Sociétés, Civilisations. 27ᵉ année, N. 2, 1972. pp. 415-426