Investigation Of A Shear Force Blood Pump For Clinical Application

A blood pump was developed and studied using the shear force principle originally described in 1913 by Nikola Tesla. The blood parametric constraints, the basic theoretical flow phenomena, and mathematical design techniques found in the literature have led to a shear force blood pump development.The shear force blood pump prototype was then fabricated and studied utilizing blood analog fluid and human blood. The blood analog fluid tests indicated that the pump met the design criteria of 5 liters per minute at the design speed of 2270 RPM, which is approximately 13 percent below the design point of 120 mm Hg.Hemolysis tests were done on outdated human blood. The results show the pump had a plasma hemoglobin rise of 430 mg/dl per hour, and a plasma hemoglobin rise of 1.075 mg/dl per pump passage. The index of hemolysis was calculated at 1.43 mg/dl per liter of blood pumped.Modifications were then made to streamline the inlet configuration of the pump and to reduce the possibility for boundary layer separation at the leading edge of the discs. The hemolysis tests were then rerun using outdated human blood. The results showed improved hemolysis parameters; the rise of plasma hemoglobin per hour was 105 mg/(dl hr), the index of hemolysis was 0.35 mg/dl per liter pumped, and the plasma hemoglobin generated per pump passage was 0.26 mg/pump passage