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A level set-based interface-enriched topology optimization for the design of phononic crystals with smooth boundaries

van den Boom, S.J. (author), Abedi, Reza (author), van Keulen, A. (author), Aragon, A.M. (author)

Phononic crystals can be designed to show band gaps—ranges of frequencies whose propagation is strongly attenuated in the material. In essence, their working principle is based on destructive interference of waves reflecting from the periodic arrangement of material interfaces (i.e., Bragg scattering). Consequently, capturing accurately the...

journal article 2023

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Topology optimization of geometrically nonlinear structures using reduced-order modeling

Zhang, L. (author), Zhang, Y. (author), van Keulen, A. (author)

High computational costs are encountered in topology optimization problems of geometrically nonlinear structures since intensive use has to be made of incremental-iterative finite element simulations. To alleviate this computational intensity, reduced-order models (ROMs) are explored in this paper. The proposed method targets ROM bases...

journal article 2023

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Fabrication sequence optimization for minimizing distortion in multi-axis additive manufacturing

Wang, W. (author), van Keulen, A. (author), Wu, J. (author)

Additive manufacturing of metal parts involves phase transformations and high temperature gradients which lead to uneven thermal expansion and contraction, and, consequently, distortion of the fabricated components. The distortion has a great influence on the structural performance and dimensional accuracy, e.g., for assembly. It is therefore...

journal article 2023

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Overheating control in additive manufacturing using a 3D topology optimization method and experimental validation

Ranjan, R. (author), Chen, Z. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

Overheating is a major issue especially in metal Additive Manufacturing (AM) processes, leading to poor surface quality, lack of dimensional precision, inferior performance and/or build failures. A 3D density-based topology optimization (TO) method is presented which addresses the issue of local overheating during metal AM. This is achieved...

journal article 2023

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Towards improved porous models for solid/fluid topology optimization

Theulings, M.J.B. (author), Langelaar, Matthijs (author), van Keulen, A. (author), Maas, Robert (author)

Modeling of fluid flows in density-based topology optimization forms a longstanding challenge. Methods based on the Navier–Stokes equations with Darcy penalization (NSDP equations) are widely used in fluid topology optimization. These methods use porous materials with low permeability to represent the solid domain. Consequently, they suffer...

journal article 2023

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Controlling local overheating in topology optimization for additive manufacturing

Ranjan, R. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

A novel constraint to prevent local overheating is presented for use in topology optimization (TO). The very basis for the constraint is the Additive Manufacturing (AM) process physics. AM enables fabrication of highly complex topologically optimized designs. However, local overheating is a major concern especially in metal AM processes...

journal article 2022

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Simultaneous topology and deposition direction optimization for Wire and Arc Additive Manufacturing

Mishra, V. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

A remarkable elastic anisotropy in plates of austenitic stainless steel produced by the Wire and Arc Additive Manufacturing process is recently reported. The Young's modulus depends on the angle of orientation with respect to the material deposition direction. Here, for the first time, this anisotropy is exploited to maximize structural...

journal article 2022

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A simple and versatile topology optimization formulation for flexure synthesis

Koppen, S. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

High-tech equipment critically relies on flexures for precise manipulation and measurement. Through elastic deformation, flexures offer extreme position repeatability within a limited range of motion in their degrees of freedom, while constraining motion in the degrees of constraint. Topology optimization proves a prospective tool for the...

journal article 2022

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Efficient multi-partition topology optimization

Koppen, S. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

In topology optimization, the state of structures is typically obtained by numerically evaluating a discretized PDE-based model. The degrees of freedom of such a model can be partitioned in free and prescribed sets to define the boundary conditions. A multi-partition problem involves multiple partitions of the same discretization, typically...

journal article 2022

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Realization and assessment of metal additive manufacturing and topology optimization for high-precision motion systems

Delissen, A.A.T.M. (author), Boots, Elwin (author), Laro, Dick (author), Kleijnen, Harry (author), van Keulen, A. (author), Langelaar, Matthijs (author)

The design of high-precision motion stages, which must exhibit high dynamic performance, is a challenging task. Manual design is difficult, time-consuming, and leads to sub-optimal designs that fail to fully exploit the extended geometric freedom that additive manufacturing offers. By using topology optimization and incorporating all...

journal article 2022

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Design for drainability in density-based topology optimization

Giele, R.J.P. (author), van Keulen, A. (author), Langelaar, Matthijs (author)

Topology optimization methods improve the structural performance of components. However, in food processing, medical, high-precision, and other industries' designs should also fulfil the requirement of being cleanable. An important aspect of cleanability is drainability, which entails that fluids can always run off the structure under just...

journal article 2022

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A stress-based criterion to identify and control intersections in 2D compliance minimization topology optimization

Mishra, V. (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

Topology optimization typically generates designs that exhibit significant geometrical complexity, which can pose difficulties for manufacturing and assembly. The number of occurrences of an important design feature, in particular intersections, increases with geometrical complexity. Intersections are essential for load transfer in many...

journal article 2022

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Simultaneous optimization of topology and layout of modular stiffeners on shells and plates

Bakker, Coen (author), Zhang, L. (author), Higginson, Kristie (author), van Keulen, A. (author)

Stiffened shells and plates are widely used in engineering. Their performance is highly influenced by the arrangement, or layout, of stiffeners on the base shell or plate and the geometric features, or topology, of these stiffeners. Moreover, modular design is beneficial, since it allows for increased quality control and mass production. In...

journal article 2021

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Overhang control in topology optimization: a comparison of continuous front propagation-based and discrete layer-by-layer overhang control

van de Ven, E.A. (author), Maas, Robert (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

Although additive manufacturing (AM) allows for a large design freedom, there are some manufacturing limitations that have to be taken into consideration. One of the most restricting design rules is the minimum allowable overhang angle. To make topology optimization suitable for AM, several algorithms have been published to enforce a minimum...

journal article 2021

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Topology Optimization for additive manufacturing with distortion constraints

Misiun, Grzegorz (author), van de Ven, E.A. (author), Langelaar, Matthijs (author), Geijselaers, Hubert (author), van Keulen, A. (author), van den Boogaard, Ton (author), Ayas, C. (author)

An important cause of failure in powder bed additive manufacturing is the distortion of the part due to thermal shrinkage during printing and the relaxation of residual stresses after its release from the base plate. In this paper, Additive Manufacturing simulations are coupled with Topology Optimization in order to generate designs that are...

journal article 2021

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An interface-enriched generalized finite element method for level set-based topology optimization

van den Boom, S.J. (author), Zhang, J. (author), van Keulen, A. (author), Aragon, A.M. (author)

During design optimization, a smooth description of the geometry is important, especially for problems that are sensitive to the way interfaces are resolved, e.g., wave propagation or fluid-structure interaction. A level set description of the boundary, when combined with an enriched finite element formulation, offers a smoother description...

journal article 2020

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Overhang control based on front propagation in 3D topology optimization for additive manufacturing

van de Ven, E.A. (author), Maas, Robert (author), Ayas, C. (author), Langelaar, Matthijs (author), van Keulen, A. (author)

It is attractive to combine topology optimization (TO) with additive manufacturing (AM), due to the design freedom provided by AM, and the increased performance that can be achieved with TO. One important aspect is to include the design rules associated with the process restrictions of AM to prevent the requirement of relatively large support...

journal article 2020

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Efficient limitation of resonant peaks by topology optimization including modal truncation augmentation

Delissen, A.A.T.M. (author), van Keulen, A. (author), Langelaar, Matthijs (author)

In many engineering applications, the dynamic frequency response of systems is of high importance. In this paper, we focus on limiting the extreme values in frequency response functions, which occur at the eigenfrequencies of the system, better known as resonant peaks. Within an optimization, merely sampling the frequency range and limiting the...

journal article 2020

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High-precision motion system design by topology optimization considering additive manufacturing

Delissen, A.A.T.M. (author), Laro, Dick (author), Kleijnen, Harry (author), van Keulen, A. (author), Langelaar, Matthijs (author)

In the design process of high-precision motion stages, the dynamic behavior is of paramount importance. Manual design of such a stage is a time-consuming process, involving many iterations between engineers responsible for mechanics, dynamics and control. By using topology optimization in combination with additive manufacturing, post...

conference paper 2020

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Design and analysis adaptivity in multi‐resolution topology optimization

Gupta, D.K. (author), van Keulen, A. (author), Langelaar, Matthijs (author)

Multiresolution topology optimization (MTO) methods involve decoupling of the design and analysis discretizations, such that a high‐resolution design can be obtained at relatively low analysis costs. Recent studies have shown that the MTO method can be approximately 3 and 30 times faster than the traditional topology optimization method for 2D...

journal article 2020