Investigation of spiral blood flow in a model of arterial stenosis

Abstract

Abstract:The spiral component of blood flow has both beneficial and detrimental effects in human circulatory system (Stonebridge and Brophy [1]). We investigate the effects of the spiral blood flow in a model of three-dimensional arterial stenosis with a 75% cross-sectional area reduction at the centre by means of computational fluid dynamics (CFD) techniques. The standard k-ω model is employed for simulation of the blood flow for the Reynolds number of 500 and 1000. We find that for Re=500 the spiral component of the blood flow increases both the total pressure and velocity of the blood, and some significant differences are found between the wall shear stresses of the spiral and non-spiral induced flow downstream of the stenosis. The turbulent kinetic energy is reduced by the spiral flow as it induces the rotational stabilities in the forward flow. For Re=1000 the tangential component of the blood velocity is most influenced by the spiral speed, but the effect of the spiral flow on the centreline turbulent kinetic energy and shear stress is mild. The results of the effects of the spiral flow are discussed in the paper along with the relevant pathological issues.

A computational study on spiral blood flow in stenosed arteries with and without an upstream curved section

“…21 also show that the maximum TKE increases for the spiral flow (frame b), though it decreases along the centreline for the spiral flow as reported by Paul and Larman [4]. Therefore, taking only the centreline data for TKE would provide an incomplete description of the spiralling effects.…”

“…The LES results in Figure 16 clearly show that in model D1 at some places between 2D (frame d) to 5D (frame g) i.e., in the core turbulence region, the TKE increases for the spiral flow though it may decrease along the centreline as shown by Paul and Larman [4]. Also the TKE in model D2 increases at some places when a spiral effect is introduced at the inlet of the model as can be seen from Figure 17 It remains same at the corresponding locations, however, the TKE is high in the post-stenotic region between 2D (frame d) and 6D (frame h).…”

“…Stonebridge et al [3] and Paul and Larman [4] investigated spiral blood flow through stenosis and carried out turbulence analysis of the flow in stenosed artery.…”

“…On the other hand, Paul and Larman [4] studied steady spiral blood flow through a rigid stenosed pipe with 75% area reduction stenosis for Reynolds number of 500 and 1000 using k-ω model and showed most of the results including the turbulence kinetic energy along the centreline. They found the spiral flow generates less turbulence kinetic energy (TKE) than the non-spiral flow for Re = 500 and no difference between the spiral flow TKE and the non-spiral flow TKE for Re = 1000.…”

Pulsatile spiral blood flow through arterial stenosis

“…Paul and Larman (Paul & Larman, 2009) conducted work which investigates the effects of different magnitudes of spiral component in arterial stenosis using a 3D k-ω turbulence model for flows of Reynolds number 500 and 1000. The paper highlights significant differences observed on wall shear stresses for non-spiral and spiral cases, additionally increases in pressure and velocity were found present in the spiral cases and the work draws relevant pathological conclusions.…”