In this paper, an advanced low-order solid–shell formulation is presented for modeling electro-active polymers (EAPs). This advanced finite element is of great importance due to the fact that EAPs actuators are typically designed as shell-like formations, in which the application of standard finite element formulation will lead to various locking pathologies (e.g. shear locking, trapezoidal locking, volumetric locking, etc.). Thus, for alleviating the various locking pathologies, both the assumed natural inhomogeneous strains ( ANIS ) and the enhanced assumed strain ( EAS ) methods are adopted for modifying the strain measure. Within the modified kinematics, a strain energy function that accounts for the elastic and the viscoelastic response as well as the electromechanical coupling is adopted. The developed formulation is implemented in the finite-element software Abaqus for further numerical applications, in which the developed ANIS solid–shell is compared with the classical assumed natural strains solid–shell and the mixed finite element formulation.

中文翻译：

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基于假定的自然非均匀应变的固体-壳公式，用于模拟电活性聚合物的粘弹性响应

在本文中，提出了一种用于模拟电活性聚合物 (EAP) 的高级低阶固体-壳公式。这种先进的有限元非常重要，因为 EAP 执行器通常设计为壳状构造，其中标准有限元公式的应用将导致各种锁定病理（例如剪切锁定、梯形锁定、体积锁定、等等。）。因此，为了缓解各种锁定病理，采用假设自然非均匀应变（ANIS）和增强假设应变（EAS）方法来修改应变措施。在修改后的运动学中，采用了考虑弹性和粘弹性响应以及机电耦合的应变能函数。