J M T Penrose | PubMed Health

PubMed2002

Development of an accurate three-dimensional finite element knee model.

This paper presents the development of a detailed articulating three-dimensional finite-element model of the human knee, derived from MRI scan images. The model utilises precise material models and many contact interfaces in order to produce a realistic kinematic response. The behaviour of the model was examined within two fields of biomechanical simulations: general life and car-crash. These simulations were performed with the non-linear explicit dynamic code PAM-SAFE trade mark. The knee model produced results that compared favourably with existing literature. Such a model (together with other joint models that could be constructed using the same techniques) would be a valuable tool for examining new designs of prosthesis and mechanisms of injury.

Accidents, Traffic↗

PubMedDate not supplied

Fluid-solid interaction: benchmarking of an external coupling of ANSYS with CFX for cardiovascular applications.

Fluid-solid interaction is a primary feature of cardiovascular flows. There is increasing interest in the numerical solution of these systems as the extensive computational resource required for such studies becomes available. One form of coupling is an external weak coupling of separate solid and fluid mechanics codes. Information about the stress tensor and displacement vector at the wetted boundary is passed between the codes, and an iterative scheme is employed to move towards convergence of these parameters at each time step. This approach has the attraction that separate codes with the most extensive functionality for each of the separate phases can be selected, which might be important in the context of the complex rheology and contact mechanics that often feature in cardiovascular systems. Penrose and Staples describe a weak coupling of CFX for computational fluid mechanics to ANSYS for solid mechanics, based on a simple Jacobi iteration scheme. It is important to validate the coupled numerical solutions. An extensive analytical study of flow in elastic-walled tubes was carried out by Womersley in the late 1950s. This paper describes the performance of the coupling software for the straight elastic-walled tube, and compares the results with Womersley's analytical solutions. It also presents preliminary results demonstrating the application of the coupled software in the context of a stented vessel.

Arteries↗