A fluid dynamics study of the Trac catheter

A fluid mechanics study of the Trac catheter was done using a 10 x scaled model. Wall pressure distributions and particle and dye flow visualization studies show that a primary vortex develops due to the spinning tip, and a secondary flow recirculates material along the chamber wall to the base of the chamber and back to the tip. Strong, nearly instantaneous mixing occurs throughout the vortex for speeds above 50,000 rpm scaled for the full-scale catheter. Close-contact pressure studies also show that wall pressures of the order of 0.4 MPa may be obtained for a full-scale catheter.