A flow visualization study of the NCVC centrifugal blood pump.
A compact centrifugal pump, NCVC-1, has an open-type impeller with 6 curved vanes, and it is characterized by no shaft and no seal. A tunnel is placed in the center of the impeller-rotor assembly to irrigate the back space behind the rotor. To evaluate the flow, we performed 3 visualization methods: tracer, oil film, and injection streak line method. The flow, observed by the tracer method in NCVC-1, indicated little turbulence along vanes. A volute chamber proved effective to reduce vortex formation in the outlet. Oil film pattern revealed no flow separation on vanes at 5 L/min. Washout flow behind the rotor is essential to prevent thrombus formation and was shown as inward spiral flow without any stagnation. These data suggested that a combination of visualization techniques was useful to analyze various flow conditions, and the NCVC-1 has excellent flow characteristics with little turbulence and little flow stagnation, which must be beneficial to low hemolysis and high antithrombogenicity.
Araki
K
K
Department of Artificial Organs, National Cardiovascular Center Research Institute, Osaka-Suita, Japan.
Taenaka
Y
Y
Masuzawa
T
T
Tatsumi
E
E
Wakisaka
Y
Y
Watari
M
M
Nakatani
T
T
Akagi
H
H
Baba
Y
Y
Anai
H
H
D006353:Heart-Assist Devices; D008961:Models, Structural; D012212:Rheology; D014741:Video Recording