Abstract

Thromboembolism (TE) significantly limits the usefulness and safety of blood-contacting devices such as hemodialysis catheters. Computer simulation of TE can provide understanding of the process and can facilitate the design of more effective devices. Previous work conducted at BYU successfully modeled TE in a simple, two-dimensional flow cell design by adding quantitative TE code to a commercial computational fluid dynamics (CFD) package, Fluent. This two-dimensional model predicted thrombus initiation and growth and adjusted flow to accommodate thrombus geometries, but was limited by computational power and unsophisticated meshing techniques. To build upon this work, and take advantage of BYU's new supercomputing system and improvements in automatic meshing software, development of a three-dimensional computational model of thrombosis in three hemodialysis catheters designs was undertaken. Development of the computer model was beset with challenges associated with limitations in both software and hardware, but those challenges were ultimately overcome as both software and hardware evolved. Eventually, the previous C-based Fluent model was ported to the Fortran-based STAR-CD model successfully. A computer geometry of a blood flow cell matching the geometry used with the previous two-dimensional model was created, and results for that geometry using the new computer compared favorably with the results from the previous model. Catheter geometries were created using computer-aided design (CAD) software and were meshed using auto-meshing software. CFD analysis identified potentially-troublesome flow regimes in the catheter designs that coincided with thrombotic regimes observed in preliminary experiments using those same catheter designs. The TE model is now ready for application to the catheter geometries and for rigorous testing (e.g., grid-independence, in-depth comparison with quantitative experiments, etc.).

Degree

College and Department

Ira A. Fulton College of Engineering and Technology; Chemical Engineering

Rights

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