Modeling and Validation of the Human Liver and Kidney Models

The objective of this study is to develop robust finite element models of the liver and kidney. The organs are modeled for the first time as hyper viscoelastic materials and with individual constituents of each (viz. the capsule and veins). To characterize the tissues, static and dynamic experiments were performed on individual parts of the porcine abdominal organs, such as capsule, vessels and parenchyma and hyper elastic, visco elastic and hyper viscoelastic materials in the form of Ogden, Mooney Rivlin and Maxwell materials were developed for each. These material models were further used to develop the finite element model of human organs. To validate these models in vitro dynamic tests on porcine kidneys were performed, whereas dynamic impact test data from the literature on human liver were used. Experiments were reproduced with the numerical approach in the LS Dyna explicit solver. The developed models are observed to reproduce the injuries of the organ to a great extent in terms of acceleration and peak force of the impactor as well as lacerations sustained by the organ during the experiments. The developed models are robust and can be integrated with the available human body finite element models to simulate accidents and to predict or simulate injuries.