On Pulsatile, Non-Newtonian Flow in the Microcirculation,

Abstract : The flow of a Casson fluid under periodic pressure gradient in a rigid tube, in the low-frequency limit has been examined. Results show that the quasi-steady solution, where time acts as a parameter and not as an independent variable, can be used to construct accurate solutions of such a flow, which are applicable to the flow of blood in small vessels of low shear rate. As an illustration, the flow under a sinusoidal positive pressure gradient was computed for the quasi-steady theory, and the nonlinear relation between flow and instantaneous pressure gradient was clearly shown by the blunting of the flow-rate curve, which occurs when the numerical magnitude of the pressure gradient is small. (Author)