Project/Area Number |
05452152
|
Research Category |
Grant-in-Aid for General Scientific Research (B)
|
Allocation Type | Single-year Grants |
Research Field |
Fluid engineering
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Research Institution | KYOTO UNIVERSITY |
Principal Investigator |
AKAMATSU Teruaki Kyoto Univ., Faculty of Engineering, Prof., 工学部, 教授 (40025896)
|
Co-Investigator(Kenkyū-buntansha) |
SHIROYAMA T Kyoto Univ., Faculty of Engineering, Assistant, 工学部, 助手 (30263106)
TAKAHIRA H Kyoto Univ., Faculty of Engineering, Lecturer, 工学部, 講師 (80206870)
|
Project Period (FY) |
1993 – 1994
|
Project Status |
Completed (Fiscal Year 1994)
|
Budget Amount *help |
¥6,400,000 (Direct Cost: ¥6,400,000)
Fiscal Year 1994: ¥1,600,000 (Direct Cost: ¥1,600,000)
Fiscal Year 1993: ¥4,800,000 (Direct Cost: ¥4,800,000)
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Keywords | Magnetical Suspension / Centrifugal Blood Pump / Hemolysis / Pump Performance / White Thrombus / Stirling's Law / Animal Experiments / Impeller / 溶血特性 / ポンプ特性 / 循環系の同定 / 磁気浮上式 |
Research Abstract |
Centrifugal blood pumps are simple, compact, easy to handle, and cheap compared with the displacement ventricular type of artificial hearts. It is promised as an artificial heart of next generation. At present, commercially available centrifugal blood pumps have some drawbacks ; the shear stress and friction heat produced on bearing and seal cause degeneration of blood. Therefore these pumps are clinically used for short term. To overcome these drawbacks, the authors have been developing a centrifugal blood pump with magnetically suspended impeller. (1) To improve pump efficiency, we have investigated the pump performances of many kinds of impeller's blades and diffusers, and the flow in the gap between the impeller's disc and the pump housing. We could find two kinds of blades with high efficiency. One is the 16-blades with outlet angle beta=90゚ and the other 7-blades with beta=40゚. The hemolysis of these pumps is less than that of Bio-Pump. Further investigation will be necessary to determine which type is better. (2) Good washout flow is the gap between the impeller disc and the pump casing is observed by visualization. However, animal cxperiments show that white thrombus adheres to the polycarbonate surface of the impeller disc. But this problem is solved by surface polishing and coating with silicon. (3) The pump operation under the constant motor current shows the pressure-flow characteristics similar to Stirling's law. So the constant current mode is recommended hereafter. (4) Hemolysis test in the blood circuits with various kinds of orifices proves that the severe hemolysis is observed in case of the orifice with sharp corner faced upstream. This fact is verified by numerical analysis of shear stress. In conclusion, this pump proves to be very promising as blood pump for long-term use.
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