Using computational fluid dynamic for hemodialysis air chamber design modification

Abstract

Design modification is a main step in developing machines and artificial organ. A new dialysis apparatus air chamber detects clot formation and interruption of blood refining circuit. Due to using enough anticoagulant, thrombosis may occur because of vortex formed by turbulent flow. Turbulent blood flow causes to endothelial injury thus supporting the formation of a thrombus. Computational fluid dynamics can estimate the flow velocity and turbulence distribution and it can be used as applicable tool to design diagnosis and modifying. In this paper CFD simulation used to find the high turbulent intensity region within the chamber and an optimization method is adopted based on the geometry changing and trying the simulation results. The turbulent intensity is chosen as a criterion to achieving to an optimized condition. Finally, a best geometry is derived for the chamber entrance by this process and modified prototype is manufactured. This refined chamber maintains on the dialysis machine and tested for several patients with different blood characteristics. The results show that no more clot formation has been observed in this new designed chamber.