An Isotropic Hyperelastic Model of Esophagus Tissue Layers along with three-dimensional Simulation of Esophageal Peristaltic Behavior

Abstract

Understanding mechanical characterization of the esophagus tissue layers is a step forward to the development of esophageal behavior, peristaltic simulation, and advanced clinical practices. Esophagus tissue layers behave nonlinear with a large amount of malformation. In this paper, different models based on the hyperelastic theory are discussed and compared to investigate the accuracy of the simulations in esophagus tissue mechanics. The simulated tissues were assumed as nonlinear, incompressible, and homogenous isotropic material. We have used the least square method for the best curve-fitting materials corresponding to the Mooney-Rivlin, Ogden, and Neo Hookean models. The results show a perfect agreement with Ogden hyperelastic model compared to the experimental studies. Moreover, based on our results, we have developed the three-dimensional finite element (FE) models by simulation of esophageal dynamic movements. Hence, FE analyses are taken into account for both simplicity and simulation of esophageal peristaltic behavior. By the numerical solutions, an interactive coding between MATLAB and ABAQUS software have been developed to achieve our goal. Current investigation is an effort to simulate esophagus, which would be used as a predictable tool for the medical and physio-mechanical study as well as educational purposes.