Experimental evaluation of a novel swirling flow generator placed in an artery with a stenosis

Abstract It is known that the presence of a stenosis in an artery can result to blood flow separation and to formation of recirculation zones downstream the stenosis. Thus, due to both low wall shear stress (WSS) values and longer residence time, excess cholesterol is deposited on the inner surface of the vessel leading to the development of the atherosclerotic plaque. A swirling-flow generator placed upstream of the stenosis reduces the length of the recirculation zone and consequently the tendency to form atherosclerotic plaque. Initially, in a previous study, using Computational Fluid Dynamics ( CFD ) and Response Surface Methodology ( RSM ), the values of the key design parameters corresponding to the optimal design were found. In this study, based on the CFD results, the swirling-flow generator was constructed using a 3D printer and positioned downstream a stenosis in an artery-like vessel. The aim is the validation of the CFD results by experimentally investigating the flow characteristics of a blood analogue downstream the stenosis. The local velocity was measured using the μ - PIV technique. It was found that both the measured pressure values and the calculated wall shear stress values are in very good agreement (less than 10%) with the computational results. Thus, the proposed model can be considered reliable and it could be used for the design and construction of a swirl generating device which can significantly reduce the length of the recirculation zone and eventually the progression of atherosclerosis in a human artery