title: Interface dynamics in a centrifugal cell separator.
abstract: 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.
authors.affiliation: Chemical Engineering Department, Washington State University, Pullman.
authors.forename: R J
authors.initials: RJ
authors.lastname: Oxford
authors.forename: J N
authors.initials: JN
authors.lastname: Petersen
authors.forename: B J
authors.initials: BJ
authors.lastname: Van Wie
authors.forename: S L
authors.initials: SL
authors.lastname: Wooten
authors.forename: G W
authors.initials: GW
authors.lastname: Schneider
mesh_terms: 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