Simulation of active muscle model with poro-elastic passive property

In the current study the effect of poroelastic assumption on muscle’s behavior has been studied. In order to reach this goal the squid tentacle muscle while catching its prey has been simulated as a three dimensional muscle model in a finite element scheme. The muscle’s strain energy function obeys the rule presented for transversely isotropic and nearly incompressible materials. The muscle is considered to have two parts of active part and passive part. The active part with radially oriented fibers is responsible for the muscle’s contraction. The contraction in this part is simulated using the Hill’s three-element model proposed for muscle contraction. The passive part of the muscle consists of two parts of solid and fluid. The solid part is modeled as a nearly incompressible and transversely isotropic material and the fluid part follows the Darcy’s law for fluids. The results driven for poro-hyperelatics assumption of the muscle are compared to the results provided for hyperelastic material modeling and those reported by experiment. The maximum displacement of the tentacle’s tip has become closer to the experiment results while assuming the material to be poro-hyperelastic. The stress generated in the activation process has also been compared. It is indicated that the absolute value of the effective Cauchy stress is higher in poro-hyperelastic material than the hyperelastic one. According to the existence of fluid inside the muscle, it is found that the poro-hyperelastic material consideration for muscles shows a response closer to reality compared to the hyperelastic assumption.

کلیدواژه ها:

Muscle contraction ، Hyperelastic material ، poroelasticity ، Finite element analysis