International Journal of Solids and Structures最新文献_第4页

Analytical model for flexoelectric sensing of structural response considering bonding compliance 考虑粘接顺应性的结构响应柔电传感分析模型

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-30 DOI: 10.1016/j.ijsolstr.2024.113084

Flexoelectricity has generated huge interest as an alternative to piezoelectricity for developing electromechanical systems such as actuators, sensors, and energy harvesters. This article presents a generic theoretical framework for the sensing mechanism of a flexoelectric sensor bonded to a host beam through an adhesive layer. The model incorporates piezoelectric and flexoelectric effects and considers both shear-lag and peel stresses at the sensor-beam interface. The formulation also includes the electric field gradient terms that are often overlooked. Consistent one-dimensional constitutive relations and governing equations of equilibrium are derived from the electric Gibb’s energy density function and extended Hamilton’s principle. The sensor is assumed to follow the Euler–Bernoulli beam-type membrane and bending deformation behaviour. Closed-form solutions are obtained for the interfacial stresses by analytically solving a seventh-order non-homogeneous ordinary differential equation, satisfying the stress-free boundary conditions at the sensor edges. The induced electric potential at the sensor top is derived by solving a fourth-order differential equation obtained from the charge balance equation, satisfying the electric boundary conditions. For validation, the sensor output is compared with the results of the existing non-rigid bonding piezoelectric sensor model. Numerical results show a significant impact of non-rigid bonding and the electric field gradient terms on the induced electric potential. Further, the importance of bonding compliance on the interfacial stress distributions is illustrated. Finally, the effects of adhesive and transducer thicknesses on the peak amplitudes of interfacial stresses and sensory potential are presented.

挠电作为压电的替代品，在开发致动器、传感器和能量收集器等机电系统方面引起了极大的兴趣。本文为通过粘合剂层粘合到主梁上的柔电传感器的传感机制提出了一个通用理论框架。该模型包含压电和挠电效应，并考虑了传感器与横梁界面上的剪切滞后应力和剥离应力。该模型还包括经常被忽视的电场梯度项。根据电吉布斯能量密度函数和扩展的汉密尔顿原理推导出一致的一维构成关系和支配平衡方程。假定传感器遵循欧拉-伯努利梁式膜和弯曲变形行为。在满足传感器边缘无应力边界条件的前提下，通过分析求解七阶非均质常微分方程，得到了界面应力的闭式解。传感器顶部的感应电动势是通过求解电荷平衡方程得到的四阶微分方程得出的，满足电动边界条件。为进行验证，将传感器输出与现有非刚性结合压电传感器模型的结果进行了比较。数值结果表明，非刚性结合和电场梯度项对感应电动势有显著影响。此外，还说明了粘合顺应性对界面应力分布的重要性。最后，介绍了粘合剂和传感器厚度对界面应力和感应电势峰值振幅的影响。

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引用次数: 0

An alternative stress boundary condition in small deformations and its application to soft elastic composites and structures 小变形中的另一种应力边界条件及其在软弹性复合材料和结构中的应用

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-30 DOI: 10.1016/j.ijsolstr.2024.113088

Linear elasticity theory has been used extensively in the study of the elastic behavior of various perforated structures and composite materials requiring the accompaniment of appropriate boundary conditions to derive qualitatively correct and quantitatively referential solutions. When incorporating conventional boundary conditions, however, linear elasticity theory fails to predict certain essential phenomena associated with perforate structures and composite materials even when they undergo small deformations. For example, a soft elastic porous medium is appreciably stiffened when inflated despite the fact that the internal air pressure is significantly lower than the modulus of the medium itself. In this paper, we propose an improved stress boundary condition by simply incorporating a small change in the normal to the boundary during deformation. We show via numerical examples that in the context of linear elasticity theory, the use of this improved boundary condition offers the possibility of predicting the influence of initial or residual stress in a perforated structure on the elastic response of the structure to external loadings (which can never be captured with the use of conventional boundary conditions). We perform also large-deformation-based finite element simulations to verify the accuracy of the closed-form results obtained from the improved boundary condition for a soft elastic perforated structure with initial internal pressure. We believe that the idea presented in this paper will extend the applicability of linear elasticity theory and yield more accurate referential analytic results for soft elastic structures and composites.

线性弹性理论被广泛应用于研究各种穿孔结构和复合材料的弹性行为，需要适当的边界条件来得出定性正确和定量参考的解决方案。然而，在结合传统边界条件时，线性弹性理论无法预测与穿孔结构和复合材料相关的某些基本现象，即使它们发生微小变形时也是如此。例如，软弹性多孔介质在充气时会明显变硬，尽管内部气压明显低于介质本身的模量。在本文中，我们提出了一种改进的应力边界条件，只需在变形过程中加入边界法线的微小变化即可。我们通过数值示例表明，在线性弹性理论的背景下，使用这种改进的边界条件可以预测穿孔结构中的初始应力或残余应力对结构对外部载荷的弹性响应的影响（使用传统边界条件永远无法捕捉到这种影响）。我们还进行了基于大变形的有限元模拟，以验证改进边界条件对具有初始内压的软弹性穿孔结构的闭式结果的准确性。我们相信，本文提出的想法将扩展线性弹性理论的适用范围，并为软弹性结构和复合材料提供更精确的参考解析结果。

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引用次数: 0

A non-isothermal breakage-damage model for plastic-bonded granular materials incorporating temperature, pressure, and rate dependencies 包含温度、压力和速率相关性的塑性粘结颗粒材料非等温破损模型

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-29 DOI: 10.1016/j.ijsolstr.2024.113085

Plastic-bonded granular materials (PBM) are widely used in industrial sectors, including building construction, abrasive applications, and defense applications such as plastic-bonded explosives. The mechanical behavior of PBM is highly nonlinear, irreversible, rate dependent, and temperature sensitive governed by various micromechanical attributions such as grain crushing and binder damage. This paper presents a thermodynamically consistent, microstructure-informed constitutive model to capture these characteristic behaviors of PBM. Key features of the model include a breakage internal variable to upscale the grain-scale information to the continuum level and to predict grain size evolution under mechanical loading. In addition, a damage internal state variable is introduced to account for the damage, deterioration, and debonding of the binder matrix upon loading. Temperature is taken as a fundamental external state variable to handle non-isothermal loading paths. The proposed model is able to capture with good accuracy several important aspects of the mechanical properties of PBM, such as pressure-dependent elasticity, pressure-dependent yield strength, brittle-to-ductile transition, temperature dependency, and rate dependency in the post-yielding regime. The model is validated against multiple published datasets obtained from confined and unconfined compression tests, covering various PBM compositions, confining pressures, temperatures, and strain rates.

塑料粘结颗粒材料（PBM）广泛应用于工业领域，包括建筑施工、研磨应用和国防应用（如塑料粘结炸药）。PBM 的机械行为具有高度非线性、不可逆、速率依赖性和温度敏感性等特点，受晶粒破碎和粘结剂损坏等各种微观机械属性的制约。本文提出了一种热力学上一致的、以微观结构为基础的构成模型，以捕捉 PBM 的这些特征行为。该模型的主要特征包括一个断裂内部变量，用于将晶粒尺度信息提升到连续水平，并预测机械加载下的晶粒尺寸演变。此外，还引入了一个损坏内部状态变量，用于解释加载时粘合剂基体的损坏、劣化和脱粘。温度作为基本外部状态变量，用于处理非等温加载路径。所提出的模型能够准确捕捉 PBM 力学性能的几个重要方面，如压力相关弹性、压力相关屈服强度、脆性到韧性转变、温度相关性以及屈服后状态的速率相关性。该模型根据多个已公布的数据集进行了验证，这些数据集来自密闭和非密闭压缩试验，涵盖了各种 PBM 成分、密闭压力、温度和应变率。

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引用次数: 0

Does static friction information predict the onset of sliding for soft material? 静摩擦信息是否能预测软材料滑动的开始？

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-28 DOI: 10.1016/j.ijsolstr.2024.113087

Friction behavior between soft and hard materials has long been a question of great interest in the fields of artificial joints, human skin contact, robotic grippers, and others. In this study, we presented a combination of theoretical and experimental analyses to investigate the friction behavior of soft materials. Using some geometric and stick–slip features in the early stage of static friction, the friction property of the interface between a soft material and a hard material is determined. Moreover, the onset of slip, the threshold force at which a friction interface begins to slide, is also predicted by a theoretical model. The predictive ability of this model may provide insights for improving interaction property recognition, as well as for developing fine tactile feedback and dexterous operation of robotic grasping.

长期以来，软硬材料之间的摩擦行为一直是人工关节、人体皮肤接触、机器人抓手等领域备受关注的问题。在本研究中，我们结合理论和实验分析，对软材料的摩擦行为进行了研究。利用静摩擦早期的一些几何特征和粘滑特征，确定了软材料和硬材料之间界面的摩擦特性。此外，理论模型还预测了滑移的起始点，即摩擦界面开始滑动的阈值力。该模型的预测能力可为改进交互属性识别、开发精细触觉反馈和机器人抓取的灵巧操作提供启示。

引用次数: 0

Effect of path-dependent plasticity on springback in reverse bending and its application to roll forming 路径依赖塑性对反向弯曲回弹的影响及其在滚压成形中的应用

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-28 DOI: 10.1016/j.ijsolstr.2024.113079

This study investigates springback behavior in martensitic advanced high-strength steels (AHSS) undergoing pure bending and reverse bending sequences. The comparison between a conventional isotropic hardening model and the Homogeneous Anisotropic Hardening (HAH20) model had been made, which accounts for non-isotropic hardening effects. Both models were calibrated using uniaxial tensile, cyclic, and loading–unloading tests. The results show that the HAH20 model predicts a higher initial springback compared to the isotropic model. However, reverse bending significantly reduces the overall springback for both models due to a minimized recovery moment. In scenarios with reverse bending, a specific strain exists where both models predict identical springback due to the secondary Bauschinger effect in tensile stress. This phenomenon is also observed in roll forming, a sequential bending process that incorporates reverse bending steps. Experimental findings from roll forming confirm a decrease in springback after the reverse bending stage. Furthermore, the study explores the impact of non-isotropic hardening on the part crashworthiness with the calibration of cross-loading effects. The Bauschinger effect and cross-loading contraction were found to reduce the maximum crash load by 6.2%.

本研究调查了马氏体高级高强度钢（AHSS）在纯弯曲和反向弯曲序列中的回弹行为。比较了传统的各向同性硬化模型和考虑了非各向同性硬化效应的均匀各向异性硬化（HAH20）模型。使用单轴拉伸、循环和加载-卸载试验对两种模型进行了校准。结果表明，与各向同性模型相比，HAH20 模型预测的初始回弹较高。然而，由于恢复力矩最小，反向弯曲大大降低了两种模型的整体回弹。在反向弯曲的情况下，由于拉伸应力的二次鲍辛格效应，两种模型预测的回弹都相同。这种现象在滚压成形中也能观察到，滚压成形是一种包含反向弯曲步骤的连续弯曲工艺。滚压成形的实验结果证实，反向弯曲阶段后回弹会减少。此外，该研究还通过校准交叉载荷效应，探讨了非各向同性硬化对零件耐撞性的影响。研究发现，鲍辛格效应和交叉载荷收缩可将最大碰撞载荷降低 6.2%。

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引用次数: 0

Unravelling electromechanical mechanism of mechanoreceptor inspired capacitive pressure sensor considering size effect 考虑尺寸效应，揭示受机械感受器启发的电容式压力传感器的机电机制

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-24 DOI: 10.1016/j.ijsolstr.2024.113083

The rapid development of intelligent sensing technologies, including electronic skins, wearable devices and robots, has put forward an urgent demand for various tactile biomimetic sensors. However, the design of tactile sensors is mostly based on independent experimental research and lack theoretical guidance at present. In this work, drawing inspiration from human skin microstructure mechanoreceptors responsible for tactile sensation, we proposed a capacitive pressure sensor model featuring a biomimetic conformal microstructured electrode with a round-crown shape. Moreover, at the micrometer scale, size effect profoundly influences the mechanical behavior of sensing materials and microstructured devices. Firstly, we conducted in-depth research on the electromechanical behavior of conformal microstructured electrode pressure sensor, considering the size effect based on couple stress elasticity and Hertz contact theory. We validated the effectiveness of the model by comparing it with experimental and simulation results of human skin. Through numerical simulation, we further verified that the theoretical model of a single microstructured electrode can be utilized for calculating microstructured electrode arrays. Furthermore, our analysis reveals that the geometric morphology and material properties of the dielectric layer, the arrangement density of the microstructured electrode arrays, along with the radius of the round-crown shaped microstructured electrode are the dominant parameters influencing the electromechanical sensitivity through parameter analysis. Finally, we devised a high-k (high dielectric permittivity) polymer composites dielectric layer with a tunable Poisson’s ratio structure, offering a feasible approach to achieving highly sensitive capacitive microstructure sensors. This theoretical model that takes into account the size effect in microstructured electrode contact problem provides theoretical insights that can guide the optimization design of high-performance tactile sensors.

电子皮肤、可穿戴设备和机器人等智能传感技术的快速发展，对各种触觉仿生传感器提出了迫切需求。然而，目前触觉传感器的设计大多基于独立的实验研究，缺乏理论指导。在这项工作中，我们从负责触觉感受的人体皮肤微结构机械感受器中汲取灵感，提出了一种电容式压力传感器模型，其特点是具有圆冠形状的仿生物共形微结构电极。此外，在微米尺度上，尺寸效应深刻影响着传感材料和微结构器件的机械行为。首先，我们基于耦合应力弹性和赫兹接触理论，考虑尺寸效应，对保形微结构电极压力传感器的机电行为进行了深入研究。通过与人体皮肤的实验和仿真结果进行比较，我们验证了模型的有效性。通过数值模拟，我们进一步验证了单个微结构电极的理论模型可用于计算微结构电极阵列。此外，通过参数分析，我们发现介电层的几何形态和材料特性、微结构电极阵列的排列密度以及圆冠形微结构电极的半径是影响机电灵敏度的主要参数。最后，我们设计了一种具有可调泊松比结构的高 k（高介电常数）聚合物复合材料介电层，为实现高灵敏度电容式微结构传感器提供了一种可行的方法。该理论模型考虑了微结构电极接触问题中的尺寸效应，为高性能触觉传感器的优化设计提供了理论依据。

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引用次数: 0

A rheological constitutive model to predict the anisotropic biaxial bending behavior of spiral strands subjected to variable axial force 预测螺旋股在可变轴向力作用下的各向异性双轴弯曲行为的流变构成模型

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-24 DOI: 10.1016/j.ijsolstr.2024.113082

Spiral strands exhibit dissipative bending behavior when subjected to external axial force. To the best of the authors’ knowledge, only the uniaxial bending behavior of spiral strands subjected to constant axial force has been studied in the literature so far. Thanks to a recently developed mixed stress–strain driven computational homogenization for spiral strands, this paper is the first to study the biaxial bending behavior of spiral strands subjected to variable tensile force. Based on the observed anisotropic behavior, a rheological constitutive model equivalent to multilayer spiral strands is proposed to predict their behavior under such loading. For an

N_{l}

-layer strand, the proposed model consists of several angularly distributed uniaxial spring systems, referred to as a multiaxial spring system, where each uniaxial spring system consists of a spring and

N_{l}

slider-springs. In a uniaxial spring system, the spring represents the slip contribution of all wires to the bending stiffness of the strand, while each slider-spring represents the stick contribution of each layer. A major advantage of the proposed scheme is its straightforward parameter identification, requiring only several monotonic uniaxial bendings under constant axial force. The proposed rheological model has been verified against the responses obtained from the mixed stress–strain driven computational homogenization through several numerical examples. These examples consist of complex uniaxial and biaxial load cases with variable tensile force. It has been shown that the proposed scheme not only predicts the response of the strand, but also provides helpful insight into the complex underlying mechanism of spiral strands. Furthermore, the low computational cost of the proposed models makes them perfect candidates for implementation as a constitutive law in a beam model. Using a single beam with the proposed constitutive law, spiral strand simulations can be performed in a few seconds on a laptop instead of a few hours or days on a supercomputer.

螺旋股在受到外部轴向力时表现出耗散弯曲行为。据作者所知，迄今为止，文献中只研究了螺旋绞线在恒定轴向力作用下的单轴弯曲行为。得益于最近开发的螺旋钢绞线混合应力-应变驱动计算均质化技术，本文首次研究了螺旋钢绞线在可变拉力作用下的双轴弯曲行为。基于观察到的各向异性行为，本文提出了一个等效于多层螺旋绞线的流变构成模型，以预测其在此类载荷下的行为。对于 Nl 层螺旋绞线，提出的模型由多个角度分布的单轴弹簧系统组成，称为多轴弹簧系统，其中每个单轴弹簧系统由一个弹簧和 Nl 个滑块弹簧组成。在单轴弹簧系统中，弹簧代表所有导线对钢绞线弯曲刚度的滑移贡献，而每个滑块弹簧则代表每层的棍棒贡献。所提方案的一个主要优点是参数识别简单，只需在恒定轴力下进行几次单调的单轴弯曲即可。通过几个数值示例，根据混合应力-应变驱动计算均质化得到的响应，对所提出的流变模型进行了验证。这些示例包括具有可变拉力的复杂单轴和双轴载荷情况。结果表明，所提出的方案不仅能预测钢绞线的响应，还能帮助人们深入了解螺旋钢绞线复杂的内在机理。此外，所提模型的计算成本较低，因此非常适合作为梁模型的构成法则。使用带有所提出的构成法则的单梁，螺旋绞线模拟可以在笔记本电脑上几秒钟内完成，而不需要在超级计算机上花费几小时或几天的时间。

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引用次数: 0

Buckling of planar curved beams with finite prebuckling deformation 具有有限预屈曲变形的平面曲线梁的屈曲

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-22 DOI: 10.1016/j.ijsolstr.2024.113081

The serpentine structure with a sufficiently thick cross section has recently been proposed as an important design concept in stretchable electronics, which features mechanically stable in-plane deformation mechanism and very low electrical resistance, bringing unique advantages for devices compared with the traditional thin ribbon layout. However, unduly increasing the thickness is well known to sacrifice the overall flexibility and functionality of devices. Such a contradiction leads to challenges in structural stability, as a relatively thick but insufficient serpentine structure may eventually undergo the out-of-plane buckling after significant in-plane prebuckling deformation and appreciable alterations in initial configuration, which is ignored by most conventional buckling theories (CBTs) and linear buckling analysis in commercial finite element analysis software, producing intolerable errors when predicting the critical loads. In this paper, a systematic and straightforward theory considering the finite prebuckling deformation (FPD buckling theory) is established to investigate the underlying mechanism. Two sets of governing equations related to the prebuckling and FPD buckling behavior are obtained. Four representative examples, including two classical problems of planar curved beams and two typical loading conditions of serpentine structures, have been carefully studied. Comparisons with the accurate geometrically-nonlinear-analysis-based (GNAB) buckling analysis have amply demonstrated the validity of our theory in predicting the reinforcement effect of prebuckling deformation on the buckling resistance of structures. Key dimensionless geometric parameters that govern this effect have also been identified, providing direct and effective guidance for the design and optimization of stretchable electronic devices.

具有足够厚横截面的蛇形结构是最近提出的可拉伸电子器件的一个重要设计概念，它具有机械稳定的面内变形机制和极低的电阻，与传统的薄带状布局相比，为器件带来了独特的优势。然而，众所周知，过度增加厚度会牺牲器件的整体灵活性和功能性。这种矛盾导致了结构稳定性方面的挑战，因为相对较厚但不够充分的蛇形结构在经过显著的面内预屈曲变形和初始配置的明显改变后，最终可能会发生面外屈曲，而大多数传统屈曲理论（CBT）和商用有限元分析软件中的线性屈曲分析都忽略了这一点，从而在预测临界载荷时产生了不可容忍的误差。本文建立了一个考虑到有限预屈曲变形的系统而简单的理论（FPD 屈曲理论）来研究其基本机制。本文获得了与预屈曲和 FPD 屈曲行为相关的两组控制方程。仔细研究了四个具有代表性的实例，包括两个平面弯曲梁的经典问题和两个蛇形结构的典型加载条件。通过与基于几何非线性分析的精确屈曲分析（GNAB）进行比较，充分证明了我们的理论在预测预屈曲变形对结构抗屈曲性的加固效应方面的有效性。我们还确定了影响这种效应的关键无量纲几何参数，为可拉伸电子设备的设计和优化提供了直接有效的指导。

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引用次数: 0

Slip identification from HR-DIC/EBSD: Incorporating Crystal Plasticity constitutive laws 从 HR-DIC/EBSD 识别滑移：纳入晶体塑性组成规律

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-21 DOI: 10.1016/j.ijsolstr.2024.113077

It is well known that dislocation slip plays a major role in plastic deformation of polycrystals. Depending on the crystal’s symmetry, only a limited number of Slip Systems (SSs) are possible, and their activities depend on the crystal orientation with respect to the applied stress. High Resolution Digital Image Correlation (HR-DIC) can be used to get the full-field measurements of displacement fields on the surface of the strained material during an in situ tensile test, whereas the EBSD technique provides local crystallographic orientations. Therefore, coupling them can lead to full description of the local slip activities. Recently, an algorithm (named SSLIP) was proposed in the literature to automatically estimate the plastic activity from HR-DIC and EBSD data. The aim of the present paper is first to improve this algorithm so that it works for incremental straining, and to propose a way to take account for the anisotropic behaviour through a well-known set of Crystal Plasticity (CP) constitutive laws. It is shown that slip identification, together with those CP laws, can be used to estimate the tensile stress at grain scale. The influence of the DIC resolution is investigated and “correction rules” for small grains are proposed. Finally, the experimental results are compared against those found using the CP Finite Element Method (CPFEM), showing good consistency, specially in terms of active SSs and local stress.

众所周知，位错滑移在多晶体的塑性变形中起着重要作用。根据晶体的对称性，只可能存在数量有限的滑移系统（SS），其活动取决于晶体相对于外加应力的取向。高分辨率数字图像相关性（HR-DIC）可用于在原位拉伸试验中对受拉伸材料表面的位移场进行全场测量，而 EBSD 技术可提供局部晶体取向。因此，将两者结合起来可以全面描述局部滑移活动。最近，文献中提出了一种从 HR-DIC 和 EBSD 数据中自动估算塑性活动的算法（名为 SSLIP）。本文的目的首先是改进该算法，使其适用于增量应变，并提出一种方法，通过一套著名的晶体塑性（CP）构成定律来考虑各向异性行为。结果表明，滑移识别与这些 CP 定律可用于估算晶粒尺度的拉伸应力。研究了 DIC 分辨率的影响，并提出了针对小晶粒的 "修正规则"。最后，将实验结果与 CP 有限元方法（CPFEM）得出的结果进行了比较，结果显示两者具有良好的一致性，特别是在活动 SS 和局部应力方面。

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引用次数: 0

Numerical calculation for streaming potentials caused by solid deformation 固体变形引起的流势的数值计算

IF 3.4 3区工程技术 Q1 MECHANICS

International Journal of Solids and Structures

Pub Date : 2024-09-21 DOI: 10.1016/j.ijsolstr.2024.113080

When a solid is deformed by an external force, it will cause the liquid in its internal pores to flow and generate a streaming potential. To understand the streaming potentials in the pores, a numerical analysis model of solid–liquid-streaming potential coupling was proposed. To validate the model, an experiment was designed and the reliability of the model was demonstrated by comparing with the results of the experiment and a theoretical analysis respectively. Then the model was applied to numerically calculate the streaming potentials in tubes with tapered-through-hole and curved holes with different curvatures respectively. The results show that under the same external loading, the streaming potentials in a straight tapered tube increases with the decrease of tube outlet diameter and increase of the thin tube length. Another result is that the curvature of a thin bent tube or hole can also cause the increment of the streaming potential. The loading frequency also affect the streaming potential. Relatively high loading frequency results in increasing the amplitude of the streaming potential.

当固体在外力作用下发生变形时，会导致其内部孔隙中的液体流动并产生流势。为了解孔隙中的流势，提出了固液流势耦合数值分析模型。为了验证该模型，设计了一个实验，并通过与实验结果和理论分析结果的比较分别证明了该模型的可靠性。然后，应用该模型分别对不同曲率的带状通孔和弯曲孔管中的流势进行了数值计算。结果表明，在相同的外部载荷下，直锥形管内的流势随管出口直径的减小和细管长度的增加而增大。另一个结果是，弯曲细管或孔的曲率也会导致流势增加。加载频率也会影响流势。相对较高的加载频率会导致流势振幅增大。

引用次数: 0