Design of the structural arrangement for a space reflector via parametric and topology optimization

Development of the optimal structural arrangement for a reflector with the aim to improve its mass and design is of importance due to the necessity to increase areal density and decrease rigidity of the modern space antennas vehicles. Currently, CAE-systems allow to design reflectors using both traditional methods, for example, parametric optimization, and methods which are innovative in this field, such as topology optimization. The paper compares two methods of the structural arrangement design for a thin dimensionally stable reflector operating as part of a geostationary spacecraft: parametric and topology optimization. The algorithms of the structural arrangement development which include the statement of the optimization problem, geometry design and a number of check analyses are presented. A number of structural of a space reflector design under the action of loads at the stage of launch, temperature gradients at the exploitation conditions and modal analysis is performed. The designed reflectors are compared. The studies performed allowed us to develop the optimal structural arrangement for a space reflector using the parametric and topology optimization. The optimal structural arrangement for a space reflector using the optimization could be produced surface figure error (estimated in RMS) with respect to the theoretical paraboloid.

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Study of Parametric and Non-Parametric Optimization of a Rotor-Bearing System

Volume 7A: Structures and Dynamics ◽

10.1115/gt2014-25095 ◽

2014 ◽

Cited By ~ 2

Author(s):

Youngwon Hahn ◽

John I. Cofer

Keyword(s):

Topology Optimization ◽

Critical Speed ◽

Parametric Optimization ◽

Optimization Methods ◽

Optimization Process ◽

Support Structure ◽

And Topology ◽

Design Variables ◽

Rotor Bearing ◽

Non Parametric

The optimization techniques most widely used in various industrial fields for structural optimization generally can be placed into two categories: parametric optimization and non-parametric optimization. In parametric optimization, the parametric variables defining a geometric model are used as design variables. For example, all dimensions defining a structural shape in a CAD (Computer-Aided Design) system can be used as parameters in an optimization process to achieve a desired objective. In non-parametric optimization, an initial outer boundary of the geometry is defined and the optimization process either removes mass without changing the node locations in the calculation mesh (topology optimization) or directly manipulates the node locations (shape optimization) to achieve a desired objective. Nowadays, the combination of both parametric and non-parametric optimization methods can provide an attractive approach to satisfy the requirements of advanced levels of structural performance. While optimization methods have been widely used in many turbomachinery applications, such as turbine and compressor blading, combustors, and casings, in the rotordynamics field, relatively little work has been done to investigate methods for the overall optimization of rotor-bearing-support structures to achieve desired system behavior. In this paper, a combined parametric and non-parametric optimization method is applied to a rotor-bearing-support structure in order to achieve the desired critical speed and unbalance response. The bearing design variables are selected as parametric design variables and topology optimization is applied to the support structure. The entire optimization workflow is constructed in the commercial software Isight, and Abaqus and ATOM (Abaqus Topology Optimization Module) are used for rotordynamics analysis and topology optimization. The desired critical speed and unbalance response can be obtained with the optimized topology of the support structure.

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Topology and Parametric Optimization-Based Design Processes for Lightweight Structures

Applied Sciences ◽

10.3390/app10134496 ◽

2020 ◽

Vol 10 (13) ◽

pp. 4496

Author(s):

Evangelos Tyflopoulos ◽

Martin Steinert

Keyword(s):

Topology Optimization ◽

Optimization Design ◽

Parametric Optimization ◽

Optimization Procedure ◽

Optimization Approach ◽

Design Processes ◽

Initial Strength ◽

Lightweight Structures ◽

Material Optimization ◽

And Topology

Topology and Parametric Optimization are two of the most implemented material optimization approaches. However, it is not clear in the literature which optimization procedure, or possible combination of them, can lead to the best results based on material reduction and optimization time. In this paper, a quantitative comparison of different topology and parametric optimization design processes is conducted using three benchmark examples: A Hollow Plate, an L-Bracket, and a Messerschmitt–Bölkow–Blohm Beam (MBB-Beam). Ten different design processes that were developed in each case study resulted in 30 simulations in total. The design processes were clustered in three main design workflows: The Topology Optimization, the Parametric Optimization, and the Simultaneous Parametric and Topology Optimization. Their results were compared with respect to mass, stress, and time. The Simultaneous Parametric and Topology Optimization approach gave the lightest design solutions without compromising their initial strength but also increased the optimization time. The findings of this paper will help the designers in the pursuit of lightweight structures and will create the basis for the identification of the ideal material optimization procedure.

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A Modified Volumetric Penalization Method for Gray Elements Suppression

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.235.25 ◽

2012 ◽

Vol 235 ◽

pp. 25-29

Author(s):

Ming Li ◽

Wen Cheng Tang

Keyword(s):

Topology Optimization ◽

Optimization Problem ◽

Penalization Method ◽

Important Method ◽

Topology Optimization Problem ◽

Modified Method ◽

And Topology ◽

Numerical Instabilities ◽

Sinh Method ◽

Topological Form

The volumetric penalization approach is an important method for gray elements suppression in topology optimization. With the volumetric penalization approach, the topology optimization problem is consistent and regularized, and topology description is unambiguous. Considering the fact that an unreasonable topological form of structure is sometimes resulted with the traditional volumetric penalization function, a modified function is proposed. By utilizing the modified function, the gray elements are compelled to be 0 or 1, and the efficiency of optimization solving is also improved. To verify the validity of the modified method, it is compared with the famous volumetric penalization method, SINH method, through a typical example. Simultaneously, its numerical instabilities are also analyzed.

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A Variational Binary Level Set Method for Structural Topology Optimization

Communications in Computational Physics ◽

10.4208/cicp.160911.110512a ◽

2013 ◽

Vol 13 (5) ◽

pp. 1292-1308 ◽

Cited By ~ 8

Author(s):

Xiaoxia Dai ◽

Peipei Tang ◽

Xiaoliang Cheng ◽

Minghui Wu

Keyword(s):

Topology Optimization ◽

Level Set Method ◽

Level Set ◽

Fast Algorithm ◽

Optimization Problem ◽

Optimal Solution ◽

Structural Topology ◽

Piecewise Constant ◽

Topology Optimization Problem ◽

And Topology

AbstractThis paper proposes a variational binary level set method for shape and topology optimization of structural. First, a topology optimization problem is pre-sented based on the level set method and an algorithm based on binary level set method is proposed to solve such problem. Considering the difficulties of coordination between the various parameters and efficient implementation of the proposed method, we present a fast algorithm by reducing several parameters to only one parameter, which would substantially reduce the complexity of computation and make it easily and quickly to get the optimal solution. The algorithm we constructed does not need to re-initialize and can produce many new holes automatically. Furthermore, the fast algorithm allows us to avoid the update of Lagrange multiplier and easily deal with constraints, such as piecewise constant, volume and length of the interfaces. Finally, we show several optimum design examples to confirm the validity and efficiency of our method.

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Optimal Design of Aero-Engine Stator Structure with Combined Shape and Topology Optimization Method

Materials Science Forum ◽

10.4028/www.scientific.net/msf.697-698.623 ◽

2011 ◽

Vol 697-698 ◽

pp. 623-626

Author(s):

Jun Gang Yang ◽

W.H. Zhang ◽

Ji Hong Zhu

Keyword(s):

Topology Optimization ◽

Optimal Design ◽

Optimization Problem ◽

Lightweight Design ◽

Optimization Method ◽

Loading Conditions ◽

Shape And Topology Optimization ◽

And Topology ◽

Aero Engine ◽

Topology Optimization Method

In this paper, the lightweight design of an aero-engine stator structure is studied as an application case. Different kinds of loading conditions are taken into account. Mathematical formulations of the optimization problem are presented. Two optimization strategies combining shape and topology optimization are tested to get optimal design results.

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