ANALYSIS OF OSCILLATORY VISCOUS FLOW IN A TETHERED, THIN-WALLED, ELASTIC TUBE.

Abstract

AS A MODEL OF THE PULSE PROPAGATION IN ARTERIES, THE WAVE PROPAGATION THROUGH A VISCOUS INCOMPRESSIBLE FLUID CONTAINED IN A THIN-WALLED ISOTROPIC ELASTIC TUBE IS CONSIDERED THEORETICALLY.THE LONGITUDINAL MOTION OF THE TUBE IS ASSUMED TO BE CONSTRAINED BY A SIMPLE VOIGT MODEL, BECAUSE THE AORTA IS AFFECTED BY SURROUNDING TISSUE.THE BLOOD IS ASSUMED TO BE A NEWTONIAN FLUID OR POLAR FLUID WHICH CAN ALLOW HYDRODYNAMIC INTERACTIONS BETWEEN RED CELLS.THE QUALITATIVE ANALYSIS AT HIGH FREQUENCIES IS DISCUSSED ON THE BASIS OF THE PHASE VELOCITY AND TRANSMISSION PER WAVELENGTH WHICH ARE MODIFIED BY TETHERING.IT IS ALSO FOUND THAT THE AVERAGE VELOCITY OVER ONE PULSE CYCLE IS IN GOOD AGREEMENT WITH THE EXPERIMENTAL ONE.THE THEORETICAL RESULTS FOR THE FLUID RESISTANCE AND INDUCTANCE ARE COMPARED WITH THE EXPERIMENTAL DATA OBTAINED BY FRY ET AL.(1964).