For rotating blood pump, the sealing problem is a very important one to solve. In this paper, it was introduced that we designed and made a small axial flow pump, applying the magnetic coupling method. The pump consis...For rotating blood pump, the sealing problem is a very important one to solve. In this paper, it was introduced that we designed and made a small axial flow pump, applying the magnetic coupling method. The pump consisted of two pump housings, a brushless DC motor, an impeller with five wanes, a pair of magnetic discs, a spacer, an inlet and an outlet areas , bearings, a support frame, and etc. The pump is made of titanium and is 125 mm length, 147 ml volume, total 380g of weight. Performances of outputting, sealing, heat creating and damage to blood by the pump were investigated in vitro experiment. Results showed for external experiment that: (1)The pressure created by the pump was 90 mmHg, the flow rates were 1.2 L/min, 4 L/min, 5.9 L/min and 7.8 L/min correspondingly to 5000 rpm, 6000 rpm, 7000 rpm and 8000rpm rotation speeds. The hydrodynamic performance of the axial flow blood pump was enough to meet a patient need when the blood pump was used as a left ventricular assistant device. (2)The hemolysis test was studied by the normalized index of hemolysis(NIH). The NIH result of the axial flow pump was 0.08 g/100 L. (3)The outside temperature of the pump didnt change obviously in 120 hours of rotation, and the sealing function was very well.展开更多
Our study evaluated the hemodynamic performance of an axial flow blood pump surgically implanted in idealized total cavopulmonary connection(TCPC)models.This blood pump was designed to augment pressure from the inferi...Our study evaluated the hemodynamic performance of an axial flow blood pump surgically implanted in idealized total cavopulmonary connection(TCPC)models.This blood pump was designed to augment pressure from the inferior vena cava(IVC)to the pulmonary circulation.Two Fontan procedures with single and bilateral superior vena cava(SVC)were compared to fit the mechanical supported TCPC physiologies.Computational fluid dynamics(CFD)analyses of two Pump-TCPC models were performed in the analyses.Pressure-flow characteristics,energy efficiency,fluid streamlines,hemolysis and thrombosis analyses were implemented.Numerical simulations indicate that the pump produces pressure generations of 1 mm to 24 mm Hg for rotational speeds ranging from 2000 RPM to 5000 RPM and flow rates of 2 LPM to 4 LPM.Two surgical models incorporated with the pump were found to be insignificant in pressure augmentation and energy boost.The risk assessment of blood trauma and thrombosis generation was evaluated representatively through blood damage index(BDI),particle resident time(PRT)and relative resistant time(RRT).The hemolysis and thrombosis analyses declare the advantage of the pump supported bilateral SVC surgical scheme in balancing flow distribution and reducing the risk of endothelial cell destruction and trauma generation.展开更多
In order to improve the surgical treatment of the congenital heart disease patient with single ventricle defect,two axial flow blood pumps,one with diffuser and the other without diffuser,were designed and virtually i...In order to improve the surgical treatment of the congenital heart disease patient with single ventricle defect,two axial flow blood pumps,one with diffuser and the other without diffuser,were designed and virtually implanted into an idealized total cavopulmonary connection(TCPC)model to form two types of Pump-TCPC physiological structure.Computational fluid dynamics(CFD)simulationswere performed to analyze the variations of the hemodynamic characteristics,such as flow field,wall shear stress(WSS),oscillatory shear index(OSI),relative residence time(RRT),between the two Pump-TCPC models.Numerical results indicate that the Pump-TCPC with diffuser has better flow field stability,less damage on endothelial cell of vessel wall,and lower risk of vascular injury and thrombosis formation than that without diffuser.展开更多
Based on established numerical methods and hydrodynamic performance testing facilities,CFD technique are applied to improve the design of the implantable axial flow blood pump and the flow analysis.(1) Applying brus...Based on established numerical methods and hydrodynamic performance testing facilities,CFD technique are applied to improve the design of the implantable axial flow blood pump and the flow analysis.(1) Applying brushless machine magnet steel,reducing its thickness while increasing the length,the flow channel's cross-section is increased,with no space connection between the large and the small rotators,and with a cone transition segment from the bearing to the principal axis,the flow is made smoother.The rotating speed is lowered by 1000 rpm-1200 rpm under the same flow rate and pressure head,and thus the hemolysis can be avoided.(2) Different outlet stator guiding vanes are selected for the same blood pump for analyses of hydrodynamic performances and flow fields.An excellent design not only can regulate the rotating flow field into an axial one,reduce the circulation loss and improve the pump efficiency,but also can avoid backflow,vortex and secondary flow at the pump outlet,and thus the thrombus can be prevented.(3) The calf live tests show that some residual clots exist at the inner wall of the outlet connection bends,which are analyzed and explained by CFD techniques and the corresponding improvements are proposed.All results are verified by hydrodynamic performance tests and PIV flow field tests,and consistent conclusions are obtained.展开更多
This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the in...This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the inner hole of the cylinder magnet of a brushless direct current motor. The inner hole makes the main flow channel possible, while the gap between the inner end of the stator and the outer end of the cylinder magnet gives the shape of the tributary flow channel. There is no motor magnet inside the main flow channel, therefore, more blood can pass through it. The gap of the tributary flow channel is very small, but the blood flow in it is not blocked. Thus, the efficiency is increased and the volume and weight of blood pump can be reduced greatly. The outer diameter, length and weight of the manufactured implantable axial-flow blood pump are 29.6 mm, 76 mm and 158 g, respectively. The impeller spins at the speed of 9000 rpm and can generate a pressure head of 100 mmHg and a flow rate of 8 L/rain. In an animal experiment, the blood pump has been successfully applied as a Ventricular Assist Device (VAD) in the chest of a small cow. Besides a mathematical model is established to simulate the flow inside an axial-flow blood pump of implantable VAD. The numerical studies on the performance of the implantable axial-flow blood pump are carried out by combining this mathematical model and the Fluent software. The numerical results agree well with those of experiments, with the maximum error less than 10%.展开更多
基金The projectwas supported by National Nine- Five Years Foundation(96 - 90 6 - 0 2 - 14 )
文摘For rotating blood pump, the sealing problem is a very important one to solve. In this paper, it was introduced that we designed and made a small axial flow pump, applying the magnetic coupling method. The pump consisted of two pump housings, a brushless DC motor, an impeller with five wanes, a pair of magnetic discs, a spacer, an inlet and an outlet areas , bearings, a support frame, and etc. The pump is made of titanium and is 125 mm length, 147 ml volume, total 380g of weight. Performances of outputting, sealing, heat creating and damage to blood by the pump were investigated in vitro experiment. Results showed for external experiment that: (1)The pressure created by the pump was 90 mmHg, the flow rates were 1.2 L/min, 4 L/min, 5.9 L/min and 7.8 L/min correspondingly to 5000 rpm, 6000 rpm, 7000 rpm and 8000rpm rotation speeds. The hydrodynamic performance of the axial flow blood pump was enough to meet a patient need when the blood pump was used as a left ventricular assistant device. (2)The hemolysis test was studied by the normalized index of hemolysis(NIH). The NIH result of the axial flow pump was 0.08 g/100 L. (3)The outside temperature of the pump didnt change obviously in 120 hours of rotation, and the sealing function was very well.
文摘Our study evaluated the hemodynamic performance of an axial flow blood pump surgically implanted in idealized total cavopulmonary connection(TCPC)models.This blood pump was designed to augment pressure from the inferior vena cava(IVC)to the pulmonary circulation.Two Fontan procedures with single and bilateral superior vena cava(SVC)were compared to fit the mechanical supported TCPC physiologies.Computational fluid dynamics(CFD)analyses of two Pump-TCPC models were performed in the analyses.Pressure-flow characteristics,energy efficiency,fluid streamlines,hemolysis and thrombosis analyses were implemented.Numerical simulations indicate that the pump produces pressure generations of 1 mm to 24 mm Hg for rotational speeds ranging from 2000 RPM to 5000 RPM and flow rates of 2 LPM to 4 LPM.Two surgical models incorporated with the pump were found to be insignificant in pressure augmentation and energy boost.The risk assessment of blood trauma and thrombosis generation was evaluated representatively through blood damage index(BDI),particle resident time(PRT)and relative resistant time(RRT).The hemolysis and thrombosis analyses declare the advantage of the pump supported bilateral SVC surgical scheme in balancing flow distribution and reducing the risk of endothelial cell destruction and trauma generation.
基金This work has been supported by the Natural Science Foundation of China(No.11872152).
文摘In order to improve the surgical treatment of the congenital heart disease patient with single ventricle defect,two axial flow blood pumps,one with diffuser and the other without diffuser,were designed and virtually implanted into an idealized total cavopulmonary connection(TCPC)model to form two types of Pump-TCPC physiological structure.Computational fluid dynamics(CFD)simulationswere performed to analyze the variations of the hemodynamic characteristics,such as flow field,wall shear stress(WSS),oscillatory shear index(OSI),relative residence time(RRT),between the two Pump-TCPC models.Numerical results indicate that the Pump-TCPC with diffuser has better flow field stability,less damage on endothelial cell of vessel wall,and lower risk of vascular injury and thrombosis formation than that without diffuser.
基金supported by the National High Technology Research and Development Program of China (863 Program Grant No. 2007AA02Z439)The Program for Outstanding Medical Academic Leader of Shanghai
文摘Based on established numerical methods and hydrodynamic performance testing facilities,CFD technique are applied to improve the design of the implantable axial flow blood pump and the flow analysis.(1) Applying brushless machine magnet steel,reducing its thickness while increasing the length,the flow channel's cross-section is increased,with no space connection between the large and the small rotators,and with a cone transition segment from the bearing to the principal axis,the flow is made smoother.The rotating speed is lowered by 1000 rpm-1200 rpm under the same flow rate and pressure head,and thus the hemolysis can be avoided.(2) Different outlet stator guiding vanes are selected for the same blood pump for analyses of hydrodynamic performances and flow fields.An excellent design not only can regulate the rotating flow field into an axial one,reduce the circulation loss and improve the pump efficiency,but also can avoid backflow,vortex and secondary flow at the pump outlet,and thus the thrombus can be prevented.(3) The calf live tests show that some residual clots exist at the inner wall of the outlet connection bends,which are analyzed and explained by CFD techniques and the corresponding improvements are proposed.All results are verified by hydrodynamic performance tests and PIV flow field tests,and consistent conclusions are obtained.
基金supported by the National High Technology Research and Development program of China (863 Program, Grant No. 2007AA02Z439)The Program for Outstanding Medical Academic Leader of Shanghai
文摘This article presents the design of a new implantable axial-flow blood pump. The special feature of the flow channel inside the blood pump is that the blood is driven by a big-small tandem impeller installed in the inner hole of the cylinder magnet of a brushless direct current motor. The inner hole makes the main flow channel possible, while the gap between the inner end of the stator and the outer end of the cylinder magnet gives the shape of the tributary flow channel. There is no motor magnet inside the main flow channel, therefore, more blood can pass through it. The gap of the tributary flow channel is very small, but the blood flow in it is not blocked. Thus, the efficiency is increased and the volume and weight of blood pump can be reduced greatly. The outer diameter, length and weight of the manufactured implantable axial-flow blood pump are 29.6 mm, 76 mm and 158 g, respectively. The impeller spins at the speed of 9000 rpm and can generate a pressure head of 100 mmHg and a flow rate of 8 L/rain. In an animal experiment, the blood pump has been successfully applied as a Ventricular Assist Device (VAD) in the chest of a small cow. Besides a mathematical model is established to simulate the flow inside an axial-flow blood pump of implantable VAD. The numerical studies on the performance of the implantable axial-flow blood pump are carried out by combining this mathematical model and the Fluent software. The numerical results agree well with those of experiments, with the maximum error less than 10%.