Most blood pumps are designed to boost the pumping abilities of the heart by mechanical energy transfer using a rotor. Due to the nature of blood contacting devices, the various components of blood are subjected to shear stresses caused by the device. The accurate analysis and prediction of blood damage during the design phase of a device has been difficult to achieve. This has been complicated by both the inaccuracy of computer tools used to model the blood flow and the large uncertainty in the reported values of stress that damage blood components. Different components of blood, such as red blood cells, platelets and VWF (Von Willebrand Factor), have different sensitivities to shear stress. Further, the damage to blood components has been correlated to both the magnitude of the shear stress and duration of time that the components are exposed to that stress (exposure time). A device that is based on cylindrical Couette flow was developed by Rochester Institute of Technology called the Maglev (Magnetic Levitation) shearing device. This device has a magnetically suspended rotor thus reducing a major amount of friction when compared to pumps with bearings. The device is intended to have a single region of laminar Couette flow (between an inner rotating cylinder and a stationary housing) that exposes the fluid to stress. From prior work, the device was partially manufactured but never made to work. The two primary goals of this thesis are to fabricate a functional magnetically levitated shearing device to induce stress in blood and other fluids using the new fluid path design and to determine the damage done to bovine blood at different exposure and stress levels.

Library of Congress Subject Headings

Blood--Circulation, Artificial; Rotary pumps; Hemolysis and hemolysins; Reynolds stress

Publication Date


Document Type


Student Type


Degree Name

Mechanical Engineering (MS)

Department, Program, or Center

Mechanical Engineering (KGCOE)


Steven W. Day

Advisor/Committee Member

Hany Ghoneim

Advisor/Committee Member

Kathleen Lamkin-Kennard


Physical copy available from RIT's Wallace Library at QP110.A7 R34 2014


RIT – Main Campus

Plan Codes