In order to facilitate the design process and to investigate multi-domain relationships between sensor's parameters and its properties, numerical models and simulations of CNT-based structures have been carried out with the primary focus on investigation of electrical conductivity for various concentrations of CNTs within the composite material. More accurate and detailed studies include analysis of the influence of deformation on changes in conductivity. However, due to significant microstructural complexity of the system (i.e. large number of CNTs within the structure) multiscale modeling and analysis approach must be employed. The main objective of this paper is to outline an relationships between micro- and macro-structural properties of CNT-based strain sensors and to discuss guidelines for a multiscale electro-mechanical model based on the Representative Volume Element (RVE) concept. The device employs the change in electrical conductivity of a CNT-based nanocomposite under applied deformation. The study investigates the impact of various micro-scale model parameters (e.g. size of an RVE, CNTs parameters etc.), on the macro scale model. Model parameters convergence studies are performed for different geometrical properties of CNTs and for various sizes of RVEs - revealing their critical mutual relationships. Also, the impact of boundary conditions at the micro-scale RVE structure is discussed. |
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