We present a novel computational framework to simulate the electromechanical response of self-sensing carbon nanotube (CNT)-based composites experiencing fracture. The computational framework combines electrical-deformation-fracture finite element modelling with a mixed micromechanics formulation. The latter is used to estimate the constitutive properties of CNT-based composites, including the elastic tensor, fracture energy, electrical conductivity, and linear piezoresistive coefficients. These properties are inputted into a coupled electro-structural finite element model, which simulates the evolution of cracks based upon phase-field fracture. The coupled physical problem is solved in a monolithic manner, exploiting the robustness and efficiency of a quasi-Newton algorithm. 2D and 3D boundary value problems are simulated to illustrate the potential of the modelling framework in assessing the influence of defects on the electromechanical response of meso- and macro-scale smart structures. Case studies aim at shedding light into the interplay between fracture and the electromechanical material response and include parametric analyses, validation against experiments and the simulation of complex cracking conditions (multiple defects, crack merging). The presented numerical results showcase the efficiency and robustness of the computational framework, as well as its ability to model a large variety of structural configurations and damage patterns. The deformation-electrical-fracture finite element code developed is made freely available to download.
翻译:我们提出了一个新的计算框架,以模拟以自我测量的碳纳米管(CNT)为基础的发生骨折的复合材料的电动机械反应。计算框架将电离畸形-裂变固定元素模型与混合微机械配方结合起来,后者用来估计以CNT为基础的复合材料的构成特性,包括弹性抗冲、断裂能量、电导性能和线性双向相向性对等系数。这些特性被输入一个混合的电结构定点元素模型,该模型模拟以相向断裂为基础的裂缝的演变。同时,物理问题以单一的方式解决,利用准纽顿算法的稳健性和效率。2D和3D边界值问题被模拟,以说明模型框架在评估缺陷对中观和宏观智能结构的电机能反应的影响方面的潜力。案例研究旨在让断裂和电机能材料反应之间的相互作用,并包括模拟以单极模式、实验和模拟以单极方式解决同时解决的物理问题,利用准纽顿算法的稳健性和效率。2D边界值问题,模拟模拟模拟其结构结构结构结构结构的大规模变形结构结构结构结构,作为成熟的模型。