Abstract
In order to improve the antithrombogenicity of a blood pump of total artificial heart, the flow characteristics inside the blood pump of TAH were investigated. Flow pattern in the blood pump was changed by varying the major orifice direction of inflow and outflow Bjork-Shiley valves, and was analyzed by following two flow visualization techniques; The tracer method was used for quantitative analysis of flow velocity and direction on a Laser light sheet plane. A new flow visualization technique based on paint erosion has been developed to estimate the wall shear stress related to washout effect. In this method, on the assumption that the wall shear stress was reflected by the change of paint thickness, poor washout field was depicted as a paint residual place. The results were as follows; 1)The circulating flow was observed in every model which has different valve orientation., 2) Washout effect was dramatically influenced by the direction of circulating flow and a horizontally circulating flow parallel with the Diaphragm-Housing junction was of most significance for good wash-out. 3) The center of circulating flow to be at the center of the blood pump was important for even washout effect.
