Numerical Modeling and Simulation of Biomedical Devices and Underwater Biomimetic Robots

Numerical simulations are essential in different fields of engineering for several types of analysis. They help in solving complex mathematical equations that govern the behavior of physical systems whose analytical solutions might be difficult to obtain. The simulations can be used in conjunction with the experimental results to compare, study and improve physical systems. This thesis focuses on the use of computational tools for three separate systems. The first one is a static structural finite element study of a self-expandable shape memory alloy (SMA) based stent. Different structures such as cantilever and coiled geometry are studied to characterize the SMA material. The SMA material is then applied to different stages of stent deployment. The behavior of a hyper elastic material such as silicone, which is used to mimic the behavior of human tissues and in the study of underwater soft robotics is also characterized and compared through different available models. The second and third parts of this study cover underwater flow simulations for an octopus and a jellyfish-like robots. In the octopus-like robot simulation, emphasis was given to the use of dynamic meshing techniques for underwater rigid motion to capture the flow behavior. Whereas, in the jellyfish simulation, attention was given to the use of fluid-structure interaction analysis, where the flapping movement of the soft jellyfish bell segment is coupled with the surrounding fluid domain to generate the required propulsion for forward motion. The study provides insightful information on the flow behavior of unique bioinspired underwater robots.