title: Internal hydraulic loss in a seal-less centrifugal Gyro pump.
abstract: A new index "loss factor Z" defined by Eq. 1 was introduced as the absolute expression of the mock loop resistance for testing a nonpulsatile pump. [formula: see text] where gamma is specific gravity of the fluid, g is the acceleration of gravity, delta P is total pressure head, and Q is flow. Z is expected to be constant, regardless of the pumping parameters. Z values obtained in the same mock loop but with different rotary blood pumps were almost identical and were defined as Z0. New methods of analysis of the flow-restrictive conditions of various rotary blood pumps are proposed in this paper: namely, differential loss factor delta Z, and loss factor sensitivity delta Z/delta A. The proposed Z-Q curves demonstrated better performance mapping than the conventional delta P-Q curves. Delta Z is the difference between the Z-Q curves of two different pumps. A is a design parameter of the pump; therefore delta Z/delta A is a quantitative expression of the effect of the design change on the hydraulic performance. These various indices were used to analyze the internal hydraulic loss of a centrifugal pump (Gyro pump). The relationship between its gap size (rotor casing) and hydraulic performance was assessed quantitatively by these indices. In this paper, the derivation processes and above-mentioned indices are described.
authors.affiliation: Department of Surgery, Baylor College of Medicine, Houston, Texas 77030.
authors.forename: K
authors.initials: K
authors.lastname: Makinouchi
authors.forename: Y
authors.initials: Y
authors.lastname: Ohara
authors.forename: I
authors.initials: I
authors.lastname: Sakuma
authors.forename: G
authors.initials: G
authors.lastname: Damm
authors.forename: K
authors.initials: K
authors.lastname: Mizuguchi
authors.forename: T
authors.initials: T
authors.lastname: Jikuya
authors.forename: S
authors.initials: S
authors.lastname: Takatani
authors.forename: G P
authors.initials: GP
authors.lastname: Noon
authors.forename: Y
authors.initials: Y
authors.lastname: Nosé
mesh_terms: D001243:Assisted Circulation / Q000295:instrumentation*; D004868:Equipment Failure; D008962:Models, Theoretical