Biomaterial Database

Use of motor current in flow rate measurement for the magnetically suspended centrifugal blood pump. 1997

T Tsukiya, and T Akamatsu, and K Nishimura, and T Yamada, and T Nakazeki

Department of Mechanical Engineering, Kyoto University, Japan.

Indirect measurement of the flow rate of a centrifugal blood pump using the driving motor current was studied. The pump flow rate can be expressed as a function of the motor current under a given motor speed in the absence of energy loss resulting from uncertain mechanical contact friction. The magnetically suspended centrifugal blood pump (MSCP), developed by the collaboration of Kyoto University and NTN Inc., was suitable for the application of this measuring method because the impeller is suspended magnetically inside the pump housing without any mechanical contact. The effect of fluid viscosity on the pump performance was investigated in detail, and it was possible to estimate the pump flow rate and the pressure difference through the pump (from inlet port to outlet port) accurately by monitoring the motor current and speed when the kinematic viscosity of working fluids was known. The kinematic viscosity of working fluids can also be measured with the MSCP. The motor current and motor speed were monitored in a chronic animal experiment, and the estimated flow rate and pressure difference showed good correlation with directly measured data.

UI	MeSH Term	Description	Entries
D008280	Magnetics	The study of MAGNETIC PHENOMENA.	Magnetic
D011312	Pressure	A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Pressures
D002498	Centrifugation	Process of using a rotating machine to generate centrifugal force to separate substances of different densities, remove moisture, or simulate gravitational effects. It employs a large motor-driven apparatus with a long arm, at the end of which human and animal subjects, biological specimens, or equipment can be revolved and rotated at various speeds to study gravitational effects. (From Websters, 10th ed; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)
D006353	Heart-Assist Devices	Small pumps, often implantable, designed for temporarily assisting the heart, usually the LEFT VENTRICLE, to pump blood. They consist of a pumping chamber and a power source, which may be partially or totally external to the body and activated by electromagnetic motors.	Artificial Ventricle,Heart Assist Device,Heart Ventricle, Artificial,Pumps, Heart-Assist,Vascular-Assist Device,Vascular-Assist Devices,Ventricle-Assist Device,Ventricular Assist Device,Artificial Heart Ventricle,Artificial Heart Ventricles,Artificial Ventricles,Assist Device, Heart,Assist Device, Ventricular,Assist Devices, Heart,Assist Devices, Ventricular,Device, Heart Assist,Device, Heart-Assist,Device, Vascular-Assist,Device, Ventricle-Assist,Device, Ventricular Assist,Devices, Heart Assist,Devices, Heart-Assist,Devices, Vascular-Assist,Devices, Ventricle-Assist,Devices, Ventricular Assist,Heart Assist Devices,Heart Ventricles, Artificial,Heart-Assist Device,Heart-Assist Pump,Heart-Assist Pumps,Pump, Heart-Assist,Pumps, Heart Assist,Vascular Assist Device,Vascular Assist Devices,Ventricle Assist Device,Ventricle, Artificial,Ventricle, Artificial Heart,Ventricle-Assist Devices,Ventricles, Artificial,Ventricles, Artificial Heart,Ventricular Assist Devices
D006400	Hematocrit	The volume of packed RED BLOOD CELLS in a blood specimen. The volume is measured by centrifugation in a tube with graduated markings, or with automated blood cell counters. It is an indicator of erythrocyte status in disease. For example, ANEMIA shows a low value; POLYCYTHEMIA, a high value.	Erythrocyte Volume, Packed,Packed Red-Cell Volume,Erythrocyte Volumes, Packed,Hematocrits,Packed Erythrocyte Volume,Packed Erythrocyte Volumes,Packed Red Cell Volume,Packed Red-Cell Volumes,Red-Cell Volume, Packed,Red-Cell Volumes, Packed,Volume, Packed Erythrocyte,Volume, Packed Red-Cell,Volumes, Packed Erythrocyte,Volumes, Packed Red-Cell
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012756	Sheep	Any of the ruminant mammals with curved horns in the genus Ovis, family Bovidae. They possess lachrymal grooves and interdigital glands, which are absent in GOATS.	Ovis,Sheep, Dall,Dall Sheep,Ovis dalli
D014783	Viscosity	The resistance that a gaseous or liquid system offers to flow when it is subjected to shear stress. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Viscosities