Physics-informed neural networks (PINNs), which are promising tools for solving nonlinear equations in the absence of labeled data, have been successfully applied for continuum field approximation in fluid mechanics, solid mechanics, thermodynamics, and other scientific and engineering problems. However, it is equally necessary to solve discontinuous problems such as cracking behaviors in structures

Several fundamental problems in science and engineering consist of global optimization tasks involving unknown high-dimensional (black-box) functions that map a set of controllable variables to the outcomes of an expensive experiment. Bayesian Optimization (BO) techniques are known to be effective in tackling global optimization problems using a relatively small number objective function evaluations

We propose a novel framework for investigating fluid–membrane interactions involving fracture, and apply it to simulate initial stages during the bursting of a balloon. Fluid flow is computed using a stabilized space–time finite element method over a body-fitted mesh. The membrane is modelled as a hyperelastic material and the equations are solved using the standard Galerkin method. Structural failure

Since the solutions of the multi-material diffusion problems are not smooth, the general physics-informed neural network (PINN) method does not work well for this problem. In this paper, we first give the interface continuity conditions which are necessarily added to the loss function as a loss term. Then, to adapt PINN for solving the multi-material diffusion problems with a single neural network

Hole control is an important issue in topology optimization. In this work, a comprehensive study is made to address four aspects related to the hole number, shape, size and spacing control. Hole features described by level-set functions (LSFs) are introduced as design primitives and constrained for the hole control requirements in topology optimization. To be specific, the hole number is controlled

Compaction bands are tabular zones of localized compressive deformation associated with porosity and permeability reduction. Depending on their orientation, compaction bands can act as barriers to fluid flow, and can be detrimental to fluid production in oil and gas reservoirs, as well as in CO2 sequestration. The process of permeability reduction and the development of excess pore pressures during

The fatigue crack growth behavior of friction stir welded joints of AZ31 Mg alloy is investigated for three different notch locations. The extended finite element method based simulation is developed to capture the effect of stir zone on fatigue crack growth behavior. The notch locations with asymmetric material domain experience an asymmetric stress field, which leads to crack path deviation from

This work presents a study on the fatigue crack initiation in the presence of stratified surface layers (SSL) – a combination of white and brown etching layer – on rail wheels. Reproducible SSLs comparable to field samples are created by a defined mechanical load and two consecutive laser surface treatments on discs made from two wheel materials (ER7, ER9). Fatigue testing is done by a twin disc tribometer

Buckling resistance has gained significant attention in topology optimization due to its profound implications for structural designs. Despite considerable research on buckling-constrained topology optimization, maximizing the critical buckling load factor (BLF) still remains a challenging topic. In this study, an innovative algorithm that utilizes a linear material interpolation scheme is introduced

In deterministic topology optimization (TO), due to not taking into account the uncertainties of the structural system, explicitly, resulting optimal layouts may conclude in low reliable levels or unreliable optimum design conditions. The objective of reliability-based topology optimization (RBTO) is to integrate the reliability concept into topology optimization, finding the optimized structures priori

The combination of topology optimization and laser powder bed fusion (LPBF), a kind of metal additive manufacturing, has attracted attention because of its ability to manufacture complex optimal structures with metal materials. However, LPBF must satisfy geometric constraints, e.g., overhang constraint and closed cavity exclusion constraint. Several previous studies proposed the fictitious physics

The fluid dynamics of microswimmers has received attention from the fields of microbiology, microrobotics, and active matter. Microorganisms have evolved organelles termed cilia for propulsion through liquids. Each cilium periodically performs effective and recovery strokes, creating a metachronal wave as a whole and developing a propulsive force. One well-established mathematical model of ciliary

Insects, birds, and bats that power and control flight by flapping their wings perform excellent flight stability and maneuverability by rapidly and continuously varying their wing motions. This article provides an overview of the state of the art of vortex-dominated, unsteady flapping aerodynamics from the viewpoint of diversity and uniformity associated with dominant vortices, particularly of the

Bonding between layers is a critical aspect in the durability and performance of asphalt pavements. The life of the pavement can be significantly reduced due to poor bonding between bituminous mix layers. For this reason, the analysis of the link between these layers is fundamental. Thus, the aim of this work is to analyse the bonding between layers, provided by different types of emulsions, when one

Reliability analysis of engineering components or structures heavily relies on accurately estimating the fatigue properties of materials. However, significant uncertainty exists regarding the distribution form and value in fatigue data, posing significant challenges in constructing a robust probability fatigue model. To address this challenge, we propose a Bayesian model averaging (BMA) method to incorporate

In previous literature, a plateau phase in fatigue growth of impact delamination projected area in CFRP was found. Explaining this plateau phase still represents a knowledge gap. In the present work, echo-pulse and through thickness transmission ultrasonic scan inspections were combined with acoustic emission monitoring to explain this plateau phase. Before the onset of growth outside of projected

It is noteworthy to explore potential measures for further reducing the aerodynamic drag and noise of high-speed pantographs. This paper proposes a method of introducing spanwise waviness into the ...

This paper presents an adaptive stochastic isogeometric method to incorporate material uncertainties in the nonlinear bending analysis of thin functionally graded material (FGM) shells. The gradient index is modeled as a second-order random field to describe the spatial randomness of material properties. An adaptive, nested, and non-intrusive Chebyshev interpolation process based on Leja sequences

The challenge of material surface damage and spalling, caused by high-frequency, high-pressure jets owing to cavitation, remains a substantial concern. To better understand the physical mechanisms of cavitation-induced cyclic impact, we developed a multi-field-coupling framework. This framework encapsulates polymer viscoelastic-viscoplastic deformation, thermal softening, strain softening, and damage

We present a multiscale computational framework for high-pressure resin transfer molding of fiber-reinforced composites. Due to the relatively rapid speed of resin flow and the significant convective effects, this process is governed by the nonlinear steady-state Navier–Stokes equations, as opposed to the linear Stokes equations commonly adopted for the simulation of classical resin transfer molding

The effect of crack-parallel stresses on the fracture properties of quasi-brittle materials has recently received significant attention in the fracture mechanics community. A new experiment, the so-called gap test, was developed to reveal this effect. While the finite element crack band model (CBM) with the physically realistic Microplane damage model M7 was quite successful in capturing the damage

Grain size dependency of the fatigue strength was investigated using Type 316 stainless steel. The main interest of this study was to clarify the root cause of the ultimate strength dependency of fatigue strength, particularly in the high-cycle fatigue regime. Four kinds of heat treatment were applied to obtain different grain sizes. The increase in the grain size caused smaller ultimate strength.

Accurate wear debris detection is vital for diagnosing engine wear. However, due to uncertainties in debris behavior, size, and operating conditions, identifying different materials with a single s...

Non-Destructive Testing (NDT) by Eddy Currents (EC) allows for determining material properties and detecting surface and subsurface defects that can harm structural integrity of electrically conductive components. However, despite being a standard technique and with many years of accumulated experience, there are some conditions where difficulties persist, such as detecting small defects in complex

Extensions to the Roe and HLL method have been previously formulated in order to solve the Shallow Water equations in the presence of source terms. These were named the Augmented Roe (ARoe) method and the HLLS method, respectively. This paper continues developing these formulations by examining how entropy corrections can be appropriately fitted in for the ARoe method and how the HLLS method can be

The construction of high-quality parameterizations for complex domains remains a significant challenge in isogeometric analysis. To address this issue, we propose a G1-smooth parameterization method for planar domains with arbitrary topology. Firstly, we generate a coarse decomposition of the given complex shape without internal singularities utilizing the extracted skeleton of the domain. We then

A hybrid Finite Volume Method (FVM)-Smoothed Particle Hydrodynamics (SPH) approach for shock capturing in compressible fluids is presented. The Python framework Pyro2 is employed to simulate a coarse FVM mesh, while the Python framework PySPH is utilized to model the fluid in regions with high gradients through SPH particles. New FVM-SPH coupling approaches are explored, including online SPH particle

Data-driven modeling in mechanics is evolving rapidly based on recent machine learning advances, especially on artificial neural networks. As the field matures, new data and models created by different groups become available, opening possibilities for cooperative modeling. However, artificial neural networks suffer from catastrophic forgetting, i.e. they forget how to perform an old task when trained

This article presents an innovative approach for developing an efficient reduced-order model to study the dispersion of urban air pollutants. The need for real-time air quality monitoring has become increasingly important, given the rise in pollutant emissions due to urbanization and its adverse effects on human health. The proposed methodology involves solving the linear advection–diffusion problem

The computational cost of the discrete element method (DEM)-population balance model (PBM) coupled framework is predominantly attributed to DEM simulations. To overcome this challenge, coarse-grained (CG) particles have been introduced in the DEM-PBM coupled framework. In this study, we proposed a new CG-enabled DEM-PBM coupled framework that builds upon the previous work of Das et al. (Proc. R. Soc

This study focuses on predicting the fatigue life of structurally bonded joints. Herein, fatigue tests were conducted using single-lap adhesive joints subjected to varying stress ratios (R = − 1.0 and − 0.5) and cyclic frequencies (f = 2, 5, 10, and 20 Hz) with a digital image correlation to measure shear strain in adhesives. The relation between tensile–shear stress and the number of cycles to failure

Damage accumulation is nonlinear in the actual fatigue process, and the loading sequence is an important factor under variable amplitude loading. In this paper, a nonlinear fatigue damage accumulation model under variable amplitude loading considering the loading sequence effect is proposed. First, the cumulative rule of fatigue damage under variable amplitude loading is analyzed. It is suggested that

Mechanical forces generated by dynamic cellular activities play a crucial role in the morphogenesis and growth of biological tissues. While the influence of mechanics is clear, many questions arise regarding the way by which mechanical forces communicate with biological processes at the level of a confluent cell population. Some answers may be found in the development of mathematical models that are

Isogeometric collocation methods have been introduced as an alternative to isogeometric Galerkin formulations, aiming at improving the computational cost of simulation by reducing the cost of assembly of the corresponding matrices. However, in contrast to their Galerkin counterparts, collocation formulations result in non-symmetric matrices of much higher dimensions, for a specified level of accuracy

In this paper, a peridynamic-enhanced finite element formulation is introduced for the numerical simulation of thermo–hydro–mechanical coupled problems in saturated porous media with cracks. The proposed approach combines the Finite Element (FE) method for governing heat conduction–advection and fluid flow in the fractured porous domain, and the Peridynamic (PD) method for describing solid phase deformation

Modern computational soft-tissue mechanics models have the potential to offer unique, patient-specific diagnostic insights. The deployment of such models in clinical settings has been limited however, due to the excessive computational costs incurred when performing mechanical simulations using conventional numerical solvers. An alternative approach to obtaining results in clinically relevant time

Friction affected fatigue behavior of stud connected steel-UHPC composite structures and fatigue crack growth in studs are experimentally studied. Push-out specimens with greased interface are tested firstly to clarify the friction effects on fatigue behavior. Then, a new visualized testing is designed for visual observation of the interface response and the fatigue crack growth in studs. Finally,

The demand for high-performance materials, along with advanced synthesis technologies such as additive manufacturing and 3D printing, has spurred the development of hierarchical composites with superior properties. However, computational modelling of such composites using physics-based solvers, while enabling the discovery of optimal microstructures, have prohibitively high computational cost hindering

Predictive modeling in physical science and engineering is mostly based on solving certain partial differential equations where the complexity of solutions is dictated by the geometry of the domain. Motivated by the broad applications of explicit solutions for spherical and ellipsoidal domains, in particular, the Eshelby’s solution in elasticity, we propose a generalization of ellipsoidal shapes called

The effect of higher order continuity in the solution field by using NURBS basis function in isogeometric analysis (IGA) is investigated for an efficient mixed finite element formulation for elastostatic beams. It is based on the Hu–Washizu variational principle considering geometrical and material nonlinearities. Here we present a reduced degree of basis functions for the additional fields of the

We propose an innovative isogeometric space–time method for the heat equation, with smooth splines approximation in both space and time. To enhance the stability of the method we add a stabilizing term, based on a linear combination of high-order artificial diffusions. This term is designed in order to make the linear system lower block-triangular, that is, lower triangular with respect to time. In

Inverse homogenization in combination with contact modeling, topology optimization and shape optimization is used to design metamaterials with optimized macroscopic response. The homogenization assumes length scale separation which allows the non-linear macroscopic behavior to be obtained by analyzing a single unit cell in a lattice structure. Self contact in the unit cell, which is modeled using a

Rotating-disk flows were first considered by von Kármán in a seminal paper in 1921, where boundary layers in general were discussed and, in two of the nine sections, results for the laminar and turbulent boundary layers over a rotating disk were presented. It was not until in 1955 that flow visualization discovered the existence of stationary cross-flow vortices on the disk prior to the transition

Accurately evaluating derivatives poses a key challenge when numerically implementing complex constitutive models. This work presents an implicit stress update algorithm that utilizes the hyper dual step derivative approximation to address derivative evaluations in elastoplastic problems. Initially, the performance of various numerical differentiation methods is discussed and compared by examining

We propose a novel approach to the linear viscoelastic problem of shear-deformable geometrically exact beams. The generalized Maxwell model for one-dimensional solids is here efficiently extended to the case of arbitrarily curved beams undergoing finite displacement and rotations. High efficiency is achieved by combining a series of distinguishing features, that are: (i) the formulation is displacement-based

Vibration fatigue refers to the failure of a structure that is repeatedly subjected to loads causing resonance. The vibration fatigue performance of DD6 single crystal superalloy, an anisotropic material, is significantly affected by its various crystal orientations. This study investigates the impact of different vibration signal intensities and orientation deviation angles on the vibration fatigue

The effects of two different grain structures on fatigue crack propagation (FCP) behavior of an Al-Cu-Li alloy were investigated. The results indicate that the fibrous grained and equiaxed grained samples exhibit significantly different FCP resistances. The FCP rates are particularly different at the Paris stage at the stress intensity factor range (ΔK) is about 20 MPa∙m1/2, the equiaxed grained sample

ABSTRACT Strengthening the thermal response of Phase-Change Materials (PCMs) is an essential and active field of research with promising potential for advanced applications such as solar energy storage, building energy conservation, and thermal management in electronic devices. This article evaluates the efficacy of a new arc-shaped fin array in shell-and-tube heat storage systems to enhance the PCM

This study proposed a concrete fatigue life prediction method based on energy dissipation analysis. The fatigue life is estimated by dividing the total critical energy dissipation by the average energy dissipation per cycle. Based on a unified concrete damage model that can be applied to both monotonic and fatigue loading conditions, the total critical energy dissipation value under fatigue loading

The eXtended Finite Element Method (X-FEM) is a versatile technique to model discontinuities by enriching the trial functions with a prior solution. In the X-FEM, a crack can be explicitly represented by a set of triangles or implicit signed distances, i.e., level set functions, of the points of interest from the crack surface and the crack front. In the explicit representations, it is crucial to accurately

Determining the mathematical structure of the stored energy of hyperelastic materials that predicts the experimental data well can prove to be complicated. For instance, the mechanical response of the brain tissue exhibits a complex shear response in the combined tension/compression and shear loading. For such a loading that involves multiple components of stress, arriving at the stored energy can

The combined effects of severe plastic deformation induced by high-frequency mechanical impact (HFMI) treatment and the electric discharge surface alloying (EDSA) with chromium on the corrosion fatigue life of low-carbon S355 steel transverse non-load-carrying specimens are studied in this paper. First, for various alternations of the combined HFMI + EDSA process, the surface alloyed layer integrity

In this research, a numerical framework for hydraulic fracturing has been formulated, incorporating thermo-hydro-mechanical (THM) coupled effects. While previous studies have reported various hydraulic fracturing models based on the phase-field method, a THM coupling scheme grounded in the variational phase-field approach remains unexplored. The THM coupling is of paramount importance for understanding

We resort to game theory in order to formulate Data-Driven methods for solid mechanics in which stress and strain players pursue different objectives. The objective of the stress player is to minimize the discrepancy to a material data set, whereas the objective of the strain player is to ensure the admissibility of the mechanical state, in the sense of compatibility and equilibrium. We show that,

Physics-Informed Neural Networks (PINNs) have recently gained increasing attention in the field of topology optimization. The fusion of deep learning and topology optimization has emerged as a prominent area of insightful research, where minimization of the loss function in neural networks can be comparable to minimization of the objective function in topology optimization. Inspired by concepts of