International Journal of Engineering Science最新文献

{"title":"Tuning elliptic-particle rotation in a soft matrix by pores","authors":"Yu Chen,&nbsp;Jianyou Zhou,&nbsp;Zheng Zhong","doi":"10.1016/j.ijengsci.2025.104421","DOIUrl":"10.1016/j.ijengsci.2025.104421","url":null,"abstract":"<div><div>Soft-hard integrated composites have received much attention owing to their programmable deformation and tunable material properties. In particular, the rotation of hard inclusions in the soft matrix plays a significant role in their mechanical performance and functionality. However, existing studies on particle rotation have mostly been limited to non-porous soft matrix, while porous matrix is ubiquitous in biological materials and composite systems. In this work, a theoretical modeling framework is developed based on the complex potential method and superposition principle to quantitatively characterize the influence of pores on the rotation of elliptic rigid particles embedded in a soft matrix. Integrated with a dimensionless stiffness scale factor, the established model is capable of capturing the effect of pore-pore interactions on particle rotation. In addition, the critical inter-pore distance is established to determine when to consider the interaction among pores on particle rotation. Finite element simulations are also performed to further validate the presented model. It is found that the influence of pores on particle rotation is controlled by the redistribution of stress field induced by the particle-pore interaction. Based on the redistribution of stress field, the concept of “pressure vortex” is proposed to elucidate the tuning mechanism of pores and inclusions on particle rotation. This work is anticipated to provide significant insights into the rotation mechanics of rigid inclusions in soft porous materials and theoretical guidelines for the optimal design of soft-hard integrated flexible devices with engineered pores and porosity.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"219 ","pages":"Article 104421"},"PeriodicalIF":5.7,"publicationDate":"2025-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145577900","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical behaviors of closed-cell fluid-filled porous media with surface effects","authors":"Chenlei Yu ,&nbsp;Fei Ti ,&nbsp;Yihang Zhang ,&nbsp;Zhao Bai ,&nbsp;Runpei Yu ,&nbsp;Yifan Liu ,&nbsp;Xiangjun Peng ,&nbsp;Cunxi Dai ,&nbsp;Yongli Zhang ,&nbsp;Xin Chen","doi":"10.1016/j.ijengsci.2025.104420","DOIUrl":"10.1016/j.ijengsci.2025.104420","url":null,"abstract":"<div><div>The mechanical behaviors of closed-cell fluid-filled porous media (CFPM) with surface effects between fluid and solid matrix have been attracting researchers’ interest over the past decades. However, current theoretical and numerical methods mainly focus on the small deformation behaviors of the CFPM with uniform pore size, while neglecting several important features, such as the non-uniform distribution of pore sizes and finite deformation. These features, which are common in engineering materials like foams and soft composites, play a crucial role in their overall performance. In this paper, we propose a user-friendly simulation method in the commercial finite element software Comsol based on the weak form formulation of the problem with surface effects incorporated. We validate this method by comparing it with the theoretical solution of the deformation near a single fluid inclusion with surface effects. Predictions of our model demonstrate that surface tension inhibits the deformation of the fluid inclusion, resulting in three distinct states: normal state, growth state, and shrinkage state. Next, we employ a homogenization method to develop an approximate theoretical solution for dual-scale CFPM and examine their equivalent mechanical properties. The shear modulus of dual-scale CFPM is influenced by the compressibility of the internal fluids, in contrast to CFPM with single-sized pores. This effect arises primarily from the different deformation modes of pores at varying scales with the same surface tension, which is verified by the two-level homogenization solution. We also examined the mechanical properties of CFPM with Gaussian-distributed pore sizes, finding that surface effects are inhibited compared to single-pore-size CFPM, especially as the standard deviation of pore radii increases. Finally, we investigated the industry challenge of finite deformation of CFPM with surface effects, the approach demonstrates that the Neo-Hookean model predicted by the microstructure, based on existing effective moduli, remains accurate up to 50% strain for multiple loading cases. These results provide theoretical support and technical guidance for engineers in structural design, process optimization, and performance prediction of CFPM.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"219 ","pages":"Article 104420"},"PeriodicalIF":5.7,"publicationDate":"2025-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145527770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to ‘Lagrangian theory of extensible elastica with arbitrary undeformed shape’ [International Journal of Engineering Science 217 (2025) 104383]","authors":"Alessandro Taloni ,&nbsp;Daniele Vilone ,&nbsp;Giuseppe Ruta","doi":"10.1016/j.ijengsci.2025.104408","DOIUrl":"10.1016/j.ijengsci.2025.104408","url":null,"abstract":"","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104408"},"PeriodicalIF":5.7,"publicationDate":"2025-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145532006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Eulerian finite-deformation framework for a gradient-enhanced material softening model with a smooth elastic–plastic transition","authors":"Michal Vazana,&nbsp;Mahmood Jabareen","doi":"10.1016/j.ijengsci.2025.104405","DOIUrl":"10.1016/j.ijengsci.2025.104405","url":null,"abstract":"<div><div>In the present study, an extension of a smooth inelasticity finite-strain model to include softening based on an implicit non-local gradient-enhanced formulation is presented. The non-local formulation includes an intrinsic length-scale parameter that eliminates mesh sensitivity and allows the model to capture the realistic mechanical behavior of materials due to localization associated with strain softening. The constitutive equations are formulated in an Eulerian approach, and the transition from elastic to plastic response is smooth. The damage variable, which gradually degrades the yield strength, is computed as a function of a non-local accumulated plastic strain. A finite element formulation, which incorporates three variational fields for the equilibrium equations and an additional field for the Helmholtz type equation of the gradient-enhanced formulation, is developed. The evolution equations are numerically integrated with a strongly objective integration algorithm, and a linearization of the incremental stress update algorithm is derived. The capabilities of the developed finite element to predict the occurrence of shear bands and to display mesh-insensitivity are demonstrated by a set of numerical examples. Specifically, simulations for the patch test, objectivity test, rate of convergence test, necking of a cylindrical bar, a plate under tension, and plane strain indentation of a rigid plate into a block are presented.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"219 ","pages":"Article 104405"},"PeriodicalIF":5.7,"publicationDate":"2025-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145478835","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Eulerian formulation of a size-dependent anisotropic non-Newtonian viscous Cosserat fluid","authors":"M.B. Rubin","doi":"10.1016/j.ijengsci.2025.104418","DOIUrl":"10.1016/j.ijengsci.2025.104418","url":null,"abstract":"<div><div>An Eulerian formulation of a size-dependent three-dimensional Cosserat continuum is developed for purely mechanical response of an anisotropic non-Newtonian viscous Cosserat fluid. The constitutive equations are Eulerian in the sense that they depend only on quantities that can be determined in the current state of the fluid. The Cosserat theory admits a triad of linearly independent deformable directors vectors at each material point, which are determined by higher-order balances of director momentum. It is shown that the balance of angular momentum of the Cosserat fluid imposes a non-trivial restriction on coupling between kinetic and kinematic variables that is satisfied by the proposed constitutive equations. An analytical solution of anisotropic Newtonian viscous fluid flow in a channel demonstrates size-dependence of the pressure driving the flow that is not present in the standard solution of a simple viscous fluid.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104418"},"PeriodicalIF":5.7,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145463872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Performance analysis of an aerostatic thrust bearing lubricated by supercritical CO2 utilizing Elrod-Ng turbulence model","authors":"Yuntang Li,&nbsp;Zhitong Sun,&nbsp;Cong Zhang,&nbsp;Jie Jin,&nbsp;Yuan Chen,&nbsp;Bingqing Wang,&nbsp;Juan Feng","doi":"10.1016/j.ijengsci.2025.104407","DOIUrl":"10.1016/j.ijengsci.2025.104407","url":null,"abstract":"<div><div>An aerostatic thrust bearing lubricated by supercritical carbon dioxide (ATB-SCO₂) is ideal axial support component for the rotating shaft of an SCO₂ cycle power generator. However, little literature is related to the performance analysis of an ATB-SCO₂ and laminar model is commonly used, leading to significant errors in bearing performance predictions. In this article, the modified Reynolds equation based on Elrod-Ng turbulence model and orifice discharge equation are combined and solved by finite difference method for calculating the static performance of an ATB-SCO₂. Moreover, the turbulence effect on ATB-SCO₂ static performance is investigated by analyzing the flow field characteristics in lubricating film. The results indicate that SCO₂ on thrust plate is in a turbulent state. Load capacity and stiffness calculated by turbulence model are larger while mass flow rate is lower compared to those of obtained by laminar model. The fluid velocity varies steeply near-wall and smoothly in middle of lubricating film due to the increased effective viscosity in middle of lubricating film. Load capacity and stiffness increase with the increase of supply pressure and rotational speed, and decrease with the growth of film thickness. Furthermore, the static performance of an ATB-SCO₂ is significantly influenced by pressure-equalizing groove depth (when the depth is &lt;50 µm) and restrictor number, and the effects of pressure-equalizing groove width can be neglected.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104407"},"PeriodicalIF":5.7,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145463871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the construction of a viscoelastic constitutive model for brain tissue maximizing tension–compression asymmetry","authors":"Mani Reddipaga ,&nbsp;K. Kannan","doi":"10.1016/j.ijengsci.2025.104415","DOIUrl":"10.1016/j.ijengsci.2025.104415","url":null,"abstract":"<div><div>Human brain tissue exhibits a nonlinear viscoelastic response characterised by relaxation, creep, and loading-rate dependence. Under quasi-static conditions, its elastic behaviour shows pronounced tension–compression asymmetry and greater shear stiffness in compression than in tension under combined loading. Capturing these features with fewer parameters remains a challenge. To ensure physical consistency, isotropic hyperelastic models are required to satisfy the Baker–Ericksen (B–E) inequalities. Leveraging the physical interpretation of Lode invariants, we construct a stored energy function through a priori analysis of B–E inequalities, achieving maximal tension–compression asymmetry by satisfying these inequalities. The resulting two-parameter stored energy function is benchmarked against existing models using the nonlinear shear modulus and Mooney’s asymmetry function under uniaxial deformation. Among these, the proposed model yields a correct bounded response consistent with experimental brain tissue data. The model is then extended to viscoelasticity using K.R. Rajagopal’s thermodynamic approach, where the viscoelastic constitutive equations are derived from the two scalar functions: the stored energy and the rate of dissipation. The developed stored energy is employed for both equilibrium and non-equilibrium contributions, and a simple quadratic dissipation function is chosen. Constitutive equations are derived by extremizing the rate of dissipation function subject to constraints such as incompressibility and the second law of thermodynamics. Validation against experimental data of Budday et al. (2017) shows that the proposed four-parameter model captures key mechanical features of brain tissue, including tension–compression asymmetry, hysteresis, and relaxation, while showing closer agreement than the six-parameter Budday–Ogden model for shear superposed on tension/compression deformation.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104415"},"PeriodicalIF":5.7,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145461733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Compression-twist induced 3D mechanical metamaterial with programmable mechanical properties","authors":"Ning Cao ,&nbsp;Tongtong Liu ,&nbsp;Xingchen Chen ,&nbsp;Ying Wu ,&nbsp;Xiang Li","doi":"10.1016/j.ijengsci.2025.104406","DOIUrl":"10.1016/j.ijengsci.2025.104406","url":null,"abstract":"<div><div>Mechanical metamaterials have attracted extensive attention for their unconventional mechanical responses. Among them, compression-twist (CT) materials introduce new opportunities for programmable mechanical behavior. However, achieving continuous control of stiffness and Poisson’s ratio over wide ranges remains challenging. While negative Poisson’s ratio (NPR) metamaterials have been widely explored for their auxetic effects, their tunability and multi-physical performance are still limited. Here, we design four three-dimensional (3D) mechanical metamaterials—CT-NPR, CT-positive Poisson’s ratio (CT-PPR), augmented CT (ACT)-NPR, and ACT-PPR—by combining CT and NPR architectures. These structures exhibit tunable Poisson’s ratios and stiffness spanning over an extremely wide range. Numerical simulations and theoretical analysis reveal that CT-NPR and CT-PPR are bending-dominated with low stiffness, whereas ACT-NPR and ACT-PPR are stretching-dominated with high stiffness. Then, the metamaterials are fabricated via 3D printing, and their mechanical properties are characterized using quasi-static compression tests. Experimental results are consistent with theoretical predictions, confirming NPR behavior in CT-NPR and ACT-NPR, and positive Poisson’s ratio behavior in CT-PPR and ACT-PPR. Additionally, CT-PPR exhibits a distinctive two-step deformation process without self-contact, while energy absorption studies show that ACT-NPR achieves superior energy dissipation and CT-PPR maintains a stable deformation mode. This work provides a new framework for designing programmable mechanical metamaterials with potential applications in shape-morphing devices, energy absorbers, medical instruments, smart actuators, and crashworthy structures.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104406"},"PeriodicalIF":5.7,"publicationDate":"2025-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145448081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Static bending of micromorphic Timoshenko beams","authors":"S. El-Borgi ,&nbsp;M. Trabelssi ,&nbsp;N. Challamel ,&nbsp;J.N. Reddy","doi":"10.1016/j.ijengsci.2025.104403","DOIUrl":"10.1016/j.ijengsci.2025.104403","url":null,"abstract":"<div><div>This study develops a rigorous analytical framework for investigating the static bending behavior of micromorphic and nonlocal strain gradient Timoshenko beams, with particular emphasis on capturing size-dependent effects in micro- and nano-scale structural elements. The model is derived using a variational principle and it consists of a set of governing equations and boundary conditions that incorporate two distinct internal length-scales, one associated with nonlocal stress gradients and the other with strain gradient effects. The obtained system of two coupled differential equations governs the deflection and the rotation of the beam. Uncoupling both equations leads to sixth- and fifth-order differential equations for the deflection and the rotation, respectively. Exact solutions are obtained for standard boundary configurations, including simply-supported, clamped–clamped, and cantilever cases, under both point and distributed loads. The analytical model is shown to be theoretically equivalent to a class of two-length-scale nonlocal strain gradient theories, thereby offering a consistent and unified description of scale-dependent mechanics in microstructured beams. A distinct series-based solution is also constructed to verify the closed-form micromorphic results. Verification against established reference solutions demonstrates the accuracy and generality of the proposed model. A series of parametric studies is conducted to quantify the role of internal length-scales, revealing that the model successfully predicts both stiffening and softening trends, depending on the microstructural configuration. The derived exact solutions provide a reliable benchmark for assessing numerical schemes and serve as a foundation for further studies involving advanced materials with microstructural complexity.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104403"},"PeriodicalIF":5.7,"publicationDate":"2025-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145435048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A spectral dislocation-based framework for 3D internal fracture in layered transversely isotropic half-spaces with imperfect interfaces","authors":"A. Vattré ,&nbsp;Z. Zhang ,&nbsp;E. Pan","doi":"10.1016/j.ijengsci.2025.104404","DOIUrl":"10.1016/j.ijengsci.2025.104404","url":null,"abstract":"<div><div>A unified dislocation-based framework is developed for the three-dimensional analysis of internal and horizontal penny-shaped cracks embedded in multilayered transversely isotropic half-spaces. The proposed formulation covers all three classical fracture modes I, II, and III, while accounting for elastic mismatch, crack depth, and imperfect interfacial contact within arbitrary layup stacking sequences. The fundamental Green’s solutions, corresponding to the elastic response induced by continuous distributions of unit-concentrated dislocation sources, are expanded using a Fourier–Bessel series system of vector functions composed of longitudinal, gradient-type meridional, and curl-type torsional modal fields. This modal decomposition establishes a canonical correspondence between fracture modes and basis components, thereby enabling mixed-mode representations by linear superposition. The displacement field is represented by spectral Love-type expansion coefficients, where the Love numbers are computed only once. The unknown displacement discontinuity is discretized using a ring-wise collocation method and subsequently determined to satisfy the prescribed crack-face loading for each fracture mode. By means of the dual-variable and position technique, recursive layer-by-layer propagation schemes are constructed to ensure internal continuity conditions and to incorporate imperfect contact through normal and tangential interfacial springs, leading to stable and fast convergence for multilayered structures. Stress intensity factors and energy release rates are extracted by matching the near-tip asymptotic behavior of the displacement discontinuity, showing excellent agreement with benchmark reference solutions, and further extending to depth-dependent mode I, II, III, and mixed-mode fracture in layered configurations. The capabilities of the formulation are illustrated by examining titanium-based multilayer systems under mode I loading. The contrast between stiff and soft gradient-layered configurations reveals how stiffness variation and interfacial compliance modulate both stress concentration and crack-face separation. The soft gradient architecture, while producing a greater crack opening, yields a reduced normalized mode I stress intensity factor compared to the stiff layered configuration. The analysis emphasizes symmetry deviations, fracture-mode-dependent discontinuities, and the localized nature of displacement and stress fields. The results provide insight into internal fracture phenomena in coated structures, layered ceramics, and stratified functional materials, and support the design of multilayer systems with improved durability and damage tolerance.</div></div>","PeriodicalId":14053,"journal":{"name":"International Journal of Engineering Science","volume":"218 ","pages":"Article 104404"},"PeriodicalIF":5.7,"publicationDate":"2025-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145427962","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}