Holzapfel-Ogden anisotropic hyperelastic model

The Holzapfel-Ogden anisotropic hyperelastic model (Holzapfel and Ogden, 2009) assumes an invariant-based strain energy potential in exponential form and is popular for simulation of the passive mechanical response of myocardium tissue. The exponential terms in the strain energy potential can be linearized/approximated by polynomial functions to avoid numerical overflow when the material is stretched significantly.

The example shown in Figure 1 uses the Holzapfel-Ogden anisotropic hyperelastic model to simulate the passive mechanical response of a four-chamber heart model with a fluid cavity pressure load. The displacement field and stress field are shown in the left and right images, respectively.

Figure 1. Four-chamber heart model.