automatic shape optimization of structural components with manufacturing constraints

Abstract Among optimization procedures, mesh morphing gained a relevant position: it proved to be a suitable tool in obtaining weight and stress concentration reduction, without the need to iterate the numerical model generation. Shape modification through mesh morphing can be performed in an automatic fashion adopting two approaches: defining parameters which will describe the modified shape or exploiting results coming from numerical analyses. With this second approach, it is possible to achieve a very high automation grade: stress values retrieved on component surfaces can be successfully employed to drive the shape modification of the component itself. This 'driven-by-numerical-results' automatic approach can lead to complex optimized shapes, which can be easily achieved with modern additive manufacturing processes, but not adopting traditional manufacturing processes. In the present work a method to include manufacturing constraints in a shape optimization workflow is presented and applied to different structural optimization cases, in order to demonstrate how even manufacturing based on traditional processes can take advantage of automatic shape optimization of structural components

optimisation of industrial parts by mesh morphing enabled automatic shape sculpting

n/

cae update of cae models on actual manufactured shapes

n/

multiphysics numerical investigation on the aeroelastic stability of a le mans prototype car

Abstract In the analysis and design of racing competition cars, numerical tools allow to investigate a wide range of solutions in short time and with high confidence in results. The great available computational power permits to combine simulation software so that different physics involved can be tackled at the same time. An important class of multi-physics simulations for motor sport addresses the fluid-structure interactions happening between the aerodynamic components of the car and the surrounding flow: this interaction can induce structural deformations and vibrations which, in turn, can influence the surrounding fluxes. In this paper, the flutter analysis of the front wing splitter mounted on the 2001 Le Mans Prototype car by Dallara (LMP1) is presented. The study was set up adopting high fidelity CAE models: a 400k shell elements FEM represents the full front wing assembly including the mounting frame, a 240M cells CFD represents the full car immersed in a box shaped wind tunnel. FEM extracted structural modal shapes are mapped onto the CFD mesh adopting Radial Basis Functions (RBF) mesh morphing so that the surfaces of the CFD model can be deformed according to retained modes. Such deformation is then propagated so that the volume mesh is adapted accordingly. The elastic CFD model with modes embedded was then loaded by applying a transient signal individually to each retained mode with a smoothed step function. A Reduced Order Model (ROM) for the aerodynamics of the coupled system was then extracted combining the results of the individual transient run. The critical speed experimentally observed to be in the operating range of the car was captured by the model quite well. The same workflow was then adopted to investigate a different design in which a stiffener has been introduced to increase the first mode natural frequency from 40Hz to 49.4Hz. Flutter speed was increased and moved outside the vehicle range. The car equipped with the improved part proved to perform on the track without previously detected instabilities

Crack Propagation Analysis of Near-Surface Defects with Radial Basis Functions Mesh Morphing

Abstract Fracture mechanics analysis is nowadays adopted in several industrial fields to assess the capability of components to withstand fatigue loads. Finite Element Method (FEM) is a well-established tool for the evaluation of flaw Stress Intensity Factors (SIF) and for the survey of its propagation. Nevertheless the study of the growth of near-surface circular and elliptical cracks is still an arduous task to be faced with FEM. In fact, the interaction of the flaw with free surfaces leads the crack front to assume complex shapes, whose simulation cannot be easily accomplished. A possible answer to deal with such a problem is to use the mesh morphing technique, a nodal relocation methodology, that allows to cover different problems. In fact, with mesh morphing, it is possible to fit the baseline flaw front with the desired shape (generic shape) and to automatically simulate its evolution at a certain number of cycles. In the proposed work this approach is demonstrated exploiting ANSYS Mechanical as FEM tool and RBF Morph ACT Extension as mesh-morpher. The results of the proposed workflow are compared with those available in literature

structural assessment of tf superconducting magnet of the dtt device

n/

A natural remedy for hot-spot stresses Using advanced mesh morphing to seamlessly perform bio-inspired structural shape optimization

This paper demonstrates how the biological growth method, studied by Mattheck in the 1990s, can be easily implemented for structural shape optimization finite element method (FEM) analyses using advanced radial basis functions (RBF) mesh morphing. We use the same mechanism observed in tree trunks: hot spots of higher stresses promote material growth as well as reducing the stress itself thanks to the added thickness. Mesh morphing is a key enabler in adapting the desired shape, calculated over the surface of the finite element analysis (FEA) mesh, to the entire solid domain. According to the same principle, material can be also removed allowing for lighter structures. We first explain the method by studying a tree trunk and then through a variety of successfully addressed structural optimization challenges