Heat exchanger (HEX) design is an optimization process that seeks to maximize heat transfer between two fluids while minimizing pressure drops. There are several conceptual design methods based on integral equations that only work with specific temperature values at the inlet and outlet of the HEX. However, it is very interesting to obtain approximate temperature distributions in these early stages

This study proposes an optimization methodology to find optimal heat source paths for point-melting in Electron Beam Melting (EBM) Powder Bed Fusion (PBF) processes, aiming to reduce the need for support structures and improve print quality. The building process is simulated using a time-dependent, one-way coupled, non-linear thermo-mechanical model, assuming negligible molten flow, with elastoplastic

Unlike traditional finite element analysis, isogeometric analysis (IGA) employs the Non-Uniform Rational B-Splines (NURBS) basis functions in computer aided design (CAD) as the interpolation functions. Many researchers have shown great interest in applying isogeometric analysis to nonlinear Kirchhoff rod problems. However, most existing studies have overlooked the objectivity of isogeometric elements

We determine spatially varying discontinuous material properties using a domain-decomposition based physics-informed neural networks (PINNs) framework named the Adaptive Interface-PINNs or AdaI-PINNs (Roy et al., 2024). We propose the use of distinct neural networks for the field variables and material properties within each material, utilizing adaptive activation functions. While the neural networks

This study conducts a comprehensive numerical analysis to examine how the interphase zone influences the mechanical behavior of multiphase metal matrix composites at the microscale. A unit-cell model is developed within a finite element framework to capture the mechanical response of (a) interphase and particle deformation and damage, (b) a porous metal matrix, and (c) surface separation at two distinct

This study presents a predictive method for process-induced deformation (PID) and residual stress in a V-shaped carbon fiber reinforced thermoplastic composite (CFRTP) using sequential thermoforming simulations within integrated thermo-mechanical simulation framework implemented in ABAQUS with user-defined materials subroutine (UMAT). The FE-based thermoforming simulation incorporates theoretical models

Concrete can show an increased material strength under dynamic loading conditions, which is related to the heterogeneity at the mesoscale, as well as the rate of loading. The ability to capture this phenomenon and predict behaviour under dynamic fracture propagation is of interest to different applications. High aspect ratio interface elements are developed here for mesoscale modelling of concrete

In recent years, a new class of mixed finite elements—compatible-strain mixed finite elements (CSMFEs)—has emerged that uses the differential complex of nonlinear elasticity. Their excellent performance in benchmark problems, such as numerical stability for modeling large deformations in near-incompressible solids, makes them a promising choice for solving engineering problems. Explicit forms exist

In this study, the virtual element method (VEM) is utilized to address fine-to-coarse mesh transitions in phase-field fracture simulations for brittle, homogeneous media. The VEM discretization of the phase-field brittle damage equation is proposed, where the consistency and stability matrices of the damage sub-problem are derived by treating it as a general second-order linear elliptic equation. A

Bioinspired composite materials, such as nacre, achieve exceptional mechanical performance through the strategic arrangement of stiff and soft components. Inspired by this natural architecture, this study presents a novel finite element modeling framework for simulating staggered composites with finite-thickness interfaces. Combining continuum and cohesive elements, the model accurately captures tension-compression

The dynamic characterization of structures using discrete models, as well as the application of modal superposition to compute their dynamic response, has been rarely explored in the literature. This is at odds with the international relevance of discrete models in structural assessment, and the multiple fields of application of modal analysis and superposition, from structural health monitoring to

Gradient-enhanced regularization is a frequently utilized method for addressing numerical issues in material modeling. As a consequence of the regularization scheme, Laplacian terms will emerge in the strong form of evolution equations for additional field variables, also called internal variables. In a series of previous works, the Neighbored Element Method (NEM) was presented as a combination of

A novel computational cost-effective approach is presented for 2D elastic dynamic analysis by utilizing rotationally periodic symmetry. The proposed algorithm is developed on the platform of TPAA-SBFEM, integrating all its advantages. By recourse of TPAA, an elastic dynamic problem is converted into a series of recursive spatial problems which are solved by SBFEM. The block-circulant SBFEM global stiffness

This contribution provides a comparative numerical assessment of the two main classes of nonlocal damage models: gradient-enhanced and integral-type strategies. Particular focus is placed on their formulations, mechanical predictions and computational aspects. A constitutive model for finite strain elastoplasticity, coupled with isotropic damage, is adopted in both cases. In-depth descriptions of both

Spurious Lagrange Multipliers oscillations present a significant challenge in implicit contact dynamics simulations. To mitigate these oscillations, (Hager and Wohlmuth 2007) proposed non-standard quadrature rules for the mass matrix, developing the Q0 and Q1 modified mass matrices. This work introduces and evaluates an extension of the Q1 mass matrix to quadratic elements. Additionally, we investigate

The sintering of powder particles prior to full melting is a defining feature of the powder bed fusion with electron beam (PBF-EB) process, distinguishing it from other metal additive manufacturing techniques. Sintering involves the movement of atoms toward contact points between adjacent particles, leading to neck formation and growth. This atomic movement is driven by the high working temperatures

Model order reduction simplifies detailed and complex Finite Element (FE) models by solving a reduced set of equations, typically through projection methods. This work proposes a physics-based model order reduction technique that circumvents the need for training data to solve quasi-static geometrically non-linear solid mechanics utilizing the concept of modal derivatives. This method comprises two

This study presents advances in non-intrusive data-driven reduced order model techniques for parametric partial differential equations based on a two-stage machine learning method, using a feedforward neural network and an autoencoder after a linear dimensionality reduction. Reduced order models are important tools for enabling many query tasks, typical of uncertainty quantification, optimization,

This manuscript presents the Quantum Finite Element Method (Q-FEM) developed for use in noisy intermediate-scale quantum (NISQ) computers and employs the variational quantum linear solver (VQLS) algorithm. The proposed method leverages the classical FEM procedure to perform the unitary decomposition of the stiffness matrix and employs generator functions to design explicit quantum circuits corresponding

In the low-frequency range, time-harmonic room acoustic models are often solved numerically by discretizing the Helmholtz equation with finite element methods, resulting in the scalar acoustic pressure field. An alternative approach is to apply finite element methods to a vector-valued form of the Helmholtz equation, formulated in terms of the Lagrangian displacement field. In this case, computing

Proper Generalized Decomposition (PGD) is a Model Order Reduction (MOR) technique used in this study to solve parametric transient Thermo-Hydro-Mechanical (THM) problems in porous media, with focus on deep geological repositories. PGD enables computing real-time solutions for THM parametric problems, which are critical in applications like enhanced oil recovery, geothermal energy, and nuclear waste

The models used for damage evolution in hyperelastic regime typically depend on material parameters like dissipation and the damage threshold. The rupture of cross-linked chains is a fundamental aspect of damage in rubbery polymers. To address this, a new reduction factor has been introduced, which extends the existing damage evolution law by incorporating a polynomial order n. This formulation is

There has been an increasing interest in the constitutive modeling of dielectric elastomers due to their potential in enabling new technologies such as soft robotics, actuators and haptic devices. Under realistic time-dependent loadings, dielectric elastomers are inherently dissipative. They dissipate energy both through viscous deformation and through friction in their electric polarization process

Explicit strategies for shell dynamics are presented using 7-parameter shell elements and the Central Difference scheme. The formulation of the 7-parameter shell element is based on the widely used Enhanced Assumed Strain (EAS), allowing the use of a 3D constitutive law in the shell element without the need to condense the transverse normal stress component in the material law. The 7-parameter shell

The vibrational response of mechanical systems including four-point contact slewing bearings is heavily influenced by the stiffness and damping properties of the bearing joint itself. As an initial approach to study the dynamic response of these components, in this work several aspects are addressed. With a view toward dynamic modelling, first, a FE-based modification of the force-deflection Hertz

Traditional bilinear isoparametric coordinate systems exhibit sensitivity to mesh distortion due to their fully high-order polynomials being only equivalent to first-order polynomials in Cartesian coordinate systems when confronted with mesh distortion. This paper combines the concept of 3- and 6-component volume coordinate systems (VCS) with the generalized mixed element method to develop a novel

The finite element algorithm is developed to solve antiplane problems involving elastic domains whose boundaries or their parts are coated with thin and relatively stiff layers. These layers are modeled by the vanishing thickness Gurtin–Murdoch material surfaces that could be open or closed, and smooth or non-smooth. The governing equations for the problems are derived using variational arguments.

The study examines the shear cutting process of Advanced High Strength Steel using the Particle Finite Element Method. Shear cutting, a crucial process in sheet metal forming, often leads to microcracks and plastic deformation that degrades the material performance in subsequent applications, such as cold forming, crashworthiness, and fatigue resistance. This work utilises the Particle Finite Element

Physic-based simulation remains a key enabler for real-world ever-growing complex industrial systems especially when crucial decisions are needed. While classical approaches have proven their accuracy and robustness over the years and come with a rich mathematical foundation, they suffer from several limitations depending of the underlying physics and use cases. For instance, especially concerning

This contribution presents an improved low-order 3D finite element formulation with hourglass stabilization using automatic differentiation (AD). Here, the former Q1STc formulation is enhanced by an approximation-free computation of the inverse Jacobian. To this end, AD tools automate the computation and allow a direct evaluation of the inverse Jacobian, bypassing the need for a Taylor series expansion

Most topology optimization techniques for enhanced designs rely on the premise of deterministic loads. Nevertheless, in actuality, variables such as placements, weights, and orientations of applied loads may inadvertently fluctuate. Deterministic load-based designs may exhibit suboptimal structural performance in the presence of loading uncertainties. Uncertain aspects must be considered in topological

This paper presents an assumed enhanced strain finite element framework for simulating hydraulic fracture propagation in saturated thermoporoelastic media, considering the influence of thermal effects. The proposed approach combines classical thermoporoelasticity theory with a cohesive fracture model to describe the coupled behaviors of fluid flow, rock deformation and fracture propagation. Within

Identification and monitoring of damage have a growing importance in the maintenance of structures. A robust active sensing framework that integrates model-based inference and optimal sensor placement is proposed. By tightly coupling measured data and data acquisition scenarios, a simultaneous approach of damage estimation and sensor placement can be used to continuously and accurately assess a structure

This paper presents a robust isogeometric topology optimization (ITO) framework that integrates Isogeometric Analysis (IGA) with global stress measures to enhance both accuracy and stability in stress-related structural optimization. Non-Uniform Rational B-Splines (NURBS)-based IGA is employed to ensure higher-order continuity and refined topology representation, enabling precise stress evaluation

Given measurements from sensors and a set of standard forces, an optimization based approach to perform damage identification in structures is introduced. The key novelty lies in letting the loads and measurements to be random variables. Subsequently, the conditional-value-at-risk (CVaR) is minimized subject to the elasticity equations as constraints. CVaR is a risk measure that leads to minimization

Periodic structures have attracted interest across various fields of science and engineering due to their unique ability to manipulate wave propagation. The Wave-based Finite Element Method (WFEM) is typically employed to model such systems by relying on the dynamic behavior of a single unit cell of the lattice. However, the WFEM can face challenges in handling unit cell finite element (FE) models

Nonlinear filter earplugs are hearing protection devices that protect against high-level impulse noises while allowing communication and situational awareness. Unlike conventional passive protectors, these devices provide increasing attenuation with the impulse sound pressure level thanks to filters made of one or more small orifices. Their performances are usually assessed with experimental measurements

We propose a new shape function for a meshfree method by combining of moving Kriging (MK) and Chebyshev interpolations, referred to Chebyshev moving Kriging (CMK) interpolations. This approach improves the accuracy of the numerical solutions by using Chebyshev polynomials in place of traditional polynomials. Additionally, Chebyshev polynomials are utilized to represent a higher-order shear deformation

Fracture propagation in heterogeneous ice-rock cliffs and hanging glaciers is complicated by the presence of internal interfaces and material property mismatch, so their failure risk is difficult to assess. Despite recent advances, phase-field fracture modeling is computationally expensive for large-scale homogeneous and heterogeneous material media. Here, we present an adaptive mesh refinement algorithm

A novel 8-node hybrid stress finite element (FE) is proposed for the efficient nonlinear analysis of in-plane loaded masonry walls. To provide a robust, easy-to-characterize mechanically, and computationally efficient practice-oriented numerical framework, masonry is idealized as an elasto-plastic homogeneous continuum. Elasto-plasticity is considered at the FE level by means of a dual-decomposition

Over the past two decades, non-intrusive techniques have been used to develop reduced-order models for nonlinear structures in industrial environments. These techniques have placed a significant emphasis on a posteriori methods, which often rely on solutions derived from computationally expensive full-order models. Using a priori methods not relying on the full order model might be preferred as they

We model transient diffusion in heterogeneous materials using a novel physics-informed neural networks framework (PINNs) termed Adaptive interface physics-informed neural networks or AdaI-PINNs (Roy et al. arXiv preprint arXiv:2406.04626, 2024). AdaI-PINNs utilize different activation functions with trainable slopes tailored to each material region within the computational domain, allowing for a fully

A variety of different vascular stent designs are currently available on the market, featuring different geometries, manufacturing materials, and physical characteristics. Here, we propose a framework for designing innovative stents that replicate and enhance the mechanical properties of existing devices. The framework includes a Solid Isotropic Material with Penalization (SIMP)-based topology optimization

Previous studies have shown that the mechanical response of incompressible hyperelastic materials is affected by the occurrence of residual stresses. In the context of biological soft tissues, such residual stresses result from factors that include growth and development processes. The detailed effect of these initial stresses on mechanical behavior remains to be explored in detail. The magnitude and

The behavior of a Timoshenko concrete beam reinforced by ribbed steel rebars is a function of the cohesive interaction between the concrete and reinforcement provided via bond-slip or traction-separation law. Bond-slip interactions between top/bottom reinforcements and the concrete beam section considering the shear deformations have been studied in this paper in static loading and nonlinear material

A framework is proposed to directly calculate the stiffness matrix of a macro-element equivalent to a desired microstructure. In a sense, this approach enables the estimation of the “homogenised” properties of microstructures without using the homogenisation theory. The proposed framework is based on assumed displacement fields within equivalent macro-elements. Different displacement assumptions are

To achieve accurate finite element (FE) analysis and to capture intricate geometric features in topology optimization using the feature mapping method, it is essential to apply extreme finely discretized background FE mesh. However, this necessity comes with increased time and memory overheads and may even lead to the failure of solving 3D problems. Consequently, this paper proposes a tailored 2:1

This paper proposes a novel framework for constructing C1 smooth isogeometric functions on the planar multipatch domain. We extend the concept of C1 coupling, wherein the null space approach was used to construct geometrically continuous basis functions as linear combinations of C0 basis functions near patch junctions. However, due to the lack of continuity constraints, the resulting approximate basis

The Cracking Elements Method (CEM) is a numerical tool for simulation of quasi-brittle fracture. It neither needs remeshing, nor nodal enrichment, or a complicated crack-tracking strategy. The cracking elements used in the CEM can be considered as a special type of Galerkin finite elements. A disadvantage of the CEM is that it uses nonlinear interpolation of the displacement field (e.g. Q8 and T6 elements

A design optimization framework is proposed for process parameters in additive manufacturing. A finite element approximation of the coupled thermomechanical model is used to simulate the fused deposition of heated material and compute the objective function for each analysis. Both gradient-based and gradient-free optimization methods are developed. The gradient-based approach, which results in a balance

The present paper introduces a methodology for formulating two-dimensional structural theories featuring arbitrary kinematic fields. In the proposed approach, each displacement variable can be examined through an independent expansion function, enabling the integration of both classical and higher-order theories within a unified framework. The Carrera Unified Formulation is used to derive the governing

In this paper, a three-dimensional arbitrary Lagrangian-Eulerian (ALE) formulation based on the consistent corotational method for flexible structures' large deformation problems is proposed. In contrast with the Lagrangian formulations, the proposed formulation can accurately describe moving boundary and load problems using moving nodes. The ALE formulation for flexible structures with an arbitrarily

In this paper, an approach to model thin composite plates reinforced with curvilinear fibres is presented and applied to analyse modes of vibration. Particular attention is given to plates with non-standard geometries, which are less commonly addressed in studies on this topic. Aiming to achieve accuracy with a small number of degrees-of-freedom, the model is based on Kirchhoff’s plate theory, combined

For additive manufacturing of fiber-reinforced composites, integrated structural topology optimization and deposition path planning is critical in capturing the anisotropic material feature for designing dynamic performance-oriented structures. Hence, this paper proposes a concurrent optimization method for simultaneously optimizing the structural topology and the fiber deposition path. The Solid Orthotropic

This paper presents a computationally effective approach for crack propagation under mechanical and thermal loads based on an adaptive mesh refinement (AMR) approach tailored for our recently developed enhanced local damage model. The mesh-dependent issue encountered in the classical local theories is effectively mitigated by incorporation of fracture energy and element characteristic length into the

Fracture in quasi-brittle materials, such as refractories and reinforced concrete, involves complex mechanisms due to a progressive micro-cracking process within a fracture process zone (FPZ). This study employs Wu's phase field model (PFM) to simulate fracture behaviour in a magnesia spinel refractory. The PFM integrates fracture mechanics and damage mechanics, predicting tortuous crack patterns when

At the mesoscale, concrete is considered a three-phase composite material comprising stone, mortar, and the interfacial transition zone. Even though mortar is an important component of concrete, its material parameters have not been determined systematically, and they are often modeled by assuming that they are weaker versions of the concrete parameters. Therefore, accurately describing the role of

The mechanical behaviour of textile materials, fundamental to textile composites, is critical for designing advanced material solutions. Mechanical modelling of textiles is highly complex due to the interactions between yarns, resulting in distinct nonlinear characteristics for different textile patterns. Therefore, engineering methods are essential for analysing loading scenarios and integrating decisions