Non-Newtonian blood flow in human right coronary arteries: Transient simulations

Abstract

This study looks at pulsatile blood flow through four different right coronary arteries, which have been reconstructed from biplane angiograms. A non-Newtonian blood model (the Generalised Power Law), as well as the usual Newtonian model of blood viscosity, is used to study the wall shear stress in each of these arteries over the entire cardiac cycle. The difference between Newtonian and non-Newtonian blood models is also studied over the whole cardiac cycle using the recently generalised global non-Newtonian importance factor. In addition, the flow is studied by considering paths of massless particles introduced into the flow field. The study shows that, when studying the wall shear stress distribution for transient blood flow in arteries, the use of a Newtonian blood model is a reasonably good approximation. However, to study the flow within the artery in greater detail, a non-Newtonian model is more appropriate.

Chaotic behavior of gas bubble in non-Newtonian fluid: a numerical study

“…In more important medical applications, bubbles are used for the delivery of drugs [2][3][4], cancer treatment [5][6][7], and in the barrier opening of clogged veins and arteries [8,9]. In all of these cases, bubbles should move and grow in the blood stream and collapse in the intended location.…”

The Wall Shear Stress of a Pulsatile Blood Flow in a Patient Specific Stenotic Right Coronary Artery

“…In the past few decades, numerous clinical researches and computer simulations have been performed to study the flow phenomena in human atherosclerotic arteries and to investigate the correlation between the WSS and the intima-media thickness [1][2][3][4][5][6][7][8][9][10]. Caro et al [1] suggested that the distribution of fatty streaking in human aorta might be coincident with the regions in which the shear rate at the arterial wall is locally reduced.…”

Effect of Pulsatile Flow Waveform and Womersley Number on the Flow in Stenosed Arterial Geometry

“…The rheology of the blood, expressed by the constitutive equation, is an important fluid property that affects the computational flow prediction. Various studies have been conducted [23][24][25][26][27] assuming different non-Newtonian constitutive equations (e.g., HerschelBerkley, power law, Quemada, Casson models) for blood. On the other hand, blood behaves as a Newtonian fluid at shear rates higher than 100 s −1 [15,28].…”

“…Accordingly, many researchers have analyzed the blood flow (particularly at larger Reynolds numbers) considering the fluid to be Newtonian [9,29]. Johnston et al [26] analyzed the effect of blood rheology in four different human right coronary arteries through a transient study. They found that the Newtonian and non-Newtonian blood viscosity models predict only a little variation in the wall shear stress in the arteries though the particle paths are often predicted differently.…”

“…However, most experimental and numerical studies assumed a simple harmonic pulse upstream to the stenosis [14,16,25,37]. Johnston et al [26] and Wiwatanapataphee et al [38] performed their studies with physiological waveforms observed in the human right coronary artery, while Long et al [39] considered the volumetric flow waveform in the carotid artery, measured by the Doppler ultrasound. Mills et al [34] compared the flows with simple pulsatile waveform and physiological waveform in the canine femoral artery.…”