Computational design of an automotive twist beam

Abstract In recent years, the automotive industry has known a remarkable development in order to satisfy the customer requirements. In this paper, we will study one of the components of the automotive which is the twist beam. The study is focused on the multicriteria design of the automotive twist beam undergoing linear elastic deformation (Hooke's law). Indeed, for the design of this automotive part, there are some criteria to be considered as the rigidity (stiffness) and the resistance to fatigue. Those two criteria are known to be conflicting, therefore, our aim is to identify the Pareto front of this problem. To do this, we used a Normal Boundary Intersection (NBI) algorithm coupling with a radial basis function (RBF) metamodel in order to reduce the high calculation time needed for solving the multicriteria design problem. Otherwise, we used the free form deformation (FFD) technique for the generation of the 3D shapes of the automotive part studied during the optimization process. Highlights We model the automotive twist beam. We developed an algorithm to solve multicriteria optimization problem. We solve our industrial problem with our developed algorithm. New profiles of the twist beam are proposed.

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Computational Design Optimization for S-Ducts

Designs ◽

10.3390/designs2040036 ◽

2018 ◽

Vol 2 (4) ◽

pp. 36 ◽

Cited By ~ 2

Author(s):

Alessio D’Ambros ◽

Timoleon Kipouros ◽

Pavlos Zachos ◽

Mark Savill ◽

Ernesto Benini

Keyword(s):

Design Space ◽

Computational Design ◽

Free Form ◽

Design Parameters ◽

Heuristic Optimization ◽

Objective Functions ◽

Pressure Losses ◽

Optimization Study ◽

Free Form Deformation ◽

Computational Fluid Dynamics Cfd

In this work, we investigate the computational design of a typical S-Duct that is found in the literature. We model the design problem as a shape optimization study. The design parameters describe the 3D geometrical changes to the shape of the S-Duct and we assess the improvements to the aerodynamic behavior by considering two objective functions: the pressure losses and the swirl. The geometry management is controlled with the Free-Form Deformation (FFD) technique, the analysis of the flow is performed using steady-state computational fluid dynamics (CFD), and the exploration of the design space is achieved using the heuristic optimization algorithm Tabu Search (MOTS). The results reveal potential improvements by 14% with respect to the pressure losses and by 71% with respect to the swirl of the flow. These findings exceed by a large margin the optimality level that was achieved by other approaches in the literature. Further investigation of a range of optimum geometries is performed and reported with a detailed discussion.

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Airfoil Optimization Using Area-Preserving Free-Form Deformation

Volume 1: Advances in Aerospace Technology ◽

10.1115/imece2015-50904 ◽

2015 ◽

Author(s):

Stavros N. Leloudas ◽

Giorgos A. Strofylas ◽

Ioannis K. Nikolos

Keyword(s):

Cross Sectional Area ◽

Equality Constraint ◽

Optimization Process ◽

Free Form ◽

Sectional Area ◽

Cross Sectional ◽

Airfoil Optimization ◽

Free Form Deformation ◽

Correction Problem ◽

Area Preserving

Given the importance of structural integrity of aerodynamic shapes, the necessity of including a cross-sectional area equality constraint among other geometrical and aerodynamic ones arises during the optimization process of an airfoil. In this work an airfoil optimization scheme is presented, based on Area-Preserving Free-Form Deformation (AP FFD), which serves as an alternative technique for the fulfillment of a cross-sectional area equality constraint. The AP FFD is based on the idea of solving an area correction problem, where a minimum possible offset is applied on all free-to-move control points of the FFD lattice, subject to the area preservation constraint. Due to the linearity of the area constraint in each axis, the extraction of an inexpensive closed-form solution to the area preservation problem is possible by using Lagrange Multipliers. A parallel Differential Evolution (DE) algorithm serves as the optimizer, assisted by two Artificial Neural Networks as surrogates. The use of multiple surrogate models, in conjunction with the inexpensive solution to the area correction problem, render the optimization process time efficient. The application of the proposed methodology for wind turbine airfoil optimization demonstrates its applicability and effectiveness.

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Shape Optimization by Free-Form Deformation: Existence Results and Numerical Solution for Stokes Flows

Journal of Scientific Computing ◽

10.1007/s10915-013-9807-8 ◽

2013 ◽

Vol 60 (3) ◽

pp. 537-563 ◽

Cited By ~ 16

Author(s):

Francesco Ballarin ◽

Andrea Manzoni ◽

Gianluigi Rozza ◽

Sandro Salsa

Keyword(s):

Shape Optimization ◽

Numerical Solution ◽

Existence Results ◽

Free Form ◽

Stokes Flows ◽

Free Form Deformation

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Fully Free-Form Deformation Features (δ-F4) Incorporating Discontinuities

Volume 1: 30th Design Automation Conference ◽

10.1115/detc2004-57225 ◽

2004 ◽

Cited By ~ 2

Author(s):

Vincent Cheutet ◽

Jean-Philippe Pernot ◽

Jean-Claude Leon ◽

Bianca Falcidieno ◽

Franca Giannini

Keyword(s):

Surface Deformation ◽

Geometric Constraints ◽

Free Form ◽

Initial Surface ◽

Cad Systems ◽

Free Form Deformation ◽

Deformation Features ◽

Generate Surface ◽

Prototype Software ◽

Free Form Surfaces

To limit low-level manipulations of free-form surfaces, the concept of Fully Free Form Deformation Features (δ-F4) have been introduced. They correspond to shapes obtained by deformation of a surface area according to specified geometric constraints. In our work, we mainly focused on those features aimed at enforcing the visual effect of the so-called character lines, extensively used by designers to specify the shape of an object. Therefore, in the proposed approach, 3D lines are used to drive surface deformation over specified areas. Depending on the wished shape and reflection light effects, the insertion of character lines may generate surface tangency discontinuities. In CAD systems, such kind of discontinuities is generally created by a decomposition of the initial surface into several patches. This process can be tedious and very complex, depending on the shape of the deformation area and the desired surface continuity. Here, a method is proposed to create discontinuities on a surface, using the trimming properties of surfaces. The corresponding deformation features produce the resulting surface in a single modification step and handle simultaneously more constraints than current CAD systems. The principle of the proposed approach is based on arbitrary shaped discontinuities in the parameter domain of the surface to allow the surface exhibiting geometric discontinuities at user-prescribed points or along lines. The proposed approach is illustrated with examples obtained using our prototype software.

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