磁-液悬浮轴流泵心脏辅助装置研制  

Development of Axial Flow Pump with a Hydrodynamicmagnetically Levitated Impeller for Heart Assistance

作　　者：李国荣[1] 朱晓东[1] 郝宗超[2] 田步升[2] 陈海丰[2] 

机构地区：[1]中国医学科学院阜外心血管病医院,北京100037 [2]长治医学院附属和平医院,046002

出　　处：《中国医疗器械信息》2013年第6期20-24,共5页China Medical Device Information

摘　　要：目的:应用磁力和流体动压控制实现轴流泵叶轮的完全悬浮。材料和方法:磁-液悬浮轴流泵由轴流泵泵筒,轴流叶轮,尾导叶叶片等组成。采用约束磁力限制旋转叶轮的轴向位移,约束磁力由旋转叶轮轮毂中的永磁体与轴流泵电机定子铁芯之间通过磁相互作用产生,轴流旋转叶轮的直径小于轴流泵泵筒内径,叶片外周与轴流泵泵筒内面之间形成动压间隙,当叶轮相对于轴流泵泵筒旋转时动压间隙中的液体产生流体动压,约束叶轮的径向位移。尾导叶叶片尾导叶叶片与轴流泵泵筒内壁固定联接,由轴流泵泵筒内壁向中心伸出,无中心轮毂的机械联接,使在这一区域形成血流通道有利于冲刷防止血栓形成。结果:磁-液悬浮轴流泵样机的直径23mm,长度65mm。在输出压力100mm汞柱条件下,泵转速约14000转/分时流量可达5升/分,在轴流叶轮转速超过6000rpm使可实现稳定的磁叶悬浮,标准溶血指数达0.12g/100L。结论:我们研制的磁液悬浮轴流泵的流体力学特性和血液相容性初步达到左心辅助的要求,可进行动物体内植入实验观察其长期心脏辅助的效果。Object： To suspend the impeller of axial flow pumps by hydrodynamic, magnetically levitating field. Methods： The newly developed axial fow pump is composed of a cylindric pump house, a impeller with magnetic rotor and a diffuser. The axial displacement of the impel er is restricted by the magnetic feld formed by the rotor and the electromagnetic stator. A tiny gap, the hydrodynamic levitating gap, is formed between the blade tip of the impl er and pump house since the diameter of impel er is slightly less than the inner-diamiter of the cylindric pump house. Hydrodynamic force wil produced inside this gap on rotating of the impel er, limiting its radial movement. Thuse the impel er wil be ful y suspended by hydrodynamic––magnetical force. A outlet diffuser is arranged behind the impel er to enhance the pump effciency, with its blades projected directly from the wal of the pump house, eliminating the center hub which is usual y for holding the diffuser blades, making a hol ow space in the diffuser center. This design al ow some blood fow through the centric passage to wash out the “dead area”behind the impel er, in favor of enhancement of antithrombotic performance. Results： Currently the prototype of the hydrodynamic, magnetical levitating axial fow pump is 23mm in diameter and 65mm in length, yielding a fow rate of 5L/min at 100 mmHg pressure with a rotating speed of 14000rpm. The normalized hemolysis index （NIH） is 0.12g/100L. Conclusion： Our newly developed axial fow pump with hydrodynamic, magnetical y levitated impel er is feasible for left ventricular assistance, just for in vivo animal test in future studies.

关 键 词：心脏辅助装置 轴流泵 悬浮 研制 标准溶血指数 血液相容性 相互作用 血栓形成 

分 类 号：R54[医药卫生—心血管疾病]