Interface dynamics in a centrifugal cell separator.
Experiments were performed with bovine blood to study the response of the plasma/cell interface position to pumping rate adjustments in two single-stage (SS I and SS II) cell separation chambers. Standard clinical instrumentation and equipment and on-line computer interfacing were used to monitor and control the interface position. The data provided a quantitative description of its dynamics in the SS I and the SS II chambers. In the SS I chamber, adjustments in the flow rate caused the interface to move very slowly and in a complex manner from one steady-state operation position to another. Such behavior made both manual and computer-controlled operation very difficult. By contrast, the SS II chamber was inherently unstable for most operating conditions. We demonstrated, however, that a feedback controller could be used easily to adjust or maintain the interface position, and this system moved from one steady-state operating condition to another 10 times as fast as the system using the SS I chamber. Also, the manner in which the controller allowed the system to respond to operator requests was much simplier than that for the SS I system.
Oxford
R J
RJ
Chemical Engineering Department, Washington State University, Pullman.
Petersen
J N
JN
Van Wie
B J
BJ
Wooten
S L
SL
Schneider
G W
GW
D000818:Animals; D001781:Blood Component Removal / Q000295:instrumentation* / Q000379:methods; D001783:Blood Flow Velocity; D002417:Cattle; D002469:Cell Separation / Q000295:instrumentation* / Q000379:methods; D002498:Centrifugation / Q000295:instrumentation*; D007958:Leukocyte Count; D010976:Platelet Count