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

Abstract

Spiral and non-spiral blood flows through three-dimensional models of 75% axisymmetric arterial stenosis are investigated by using two-equation standard k-ω transitional model and Large Eddy Simulation (LES). The arterial stenosis models chosen are straight stenosed tubes without and with upstream curved segments of various angles of curvature. The Reynolds numbers investigated are 500, 1000, 1500 and 2000. Spiral effect is introduced by taking one-sixth of the bulk velocity as a tangential velocity at the inlet, and the inlet turbulence intensity was introduced for matching experimental results. LES results with a right amount of inlet turbulence intensity matches experimental results better than the k-ω results. The results show that the spiral flow affects the turbulence kinetic energy in the post stenosis region. Other important results such as the wall pressure and shear stress remain almost unchanged by the spiral velocity. But the presence of the upstream curved segment in artery moderately affects the results of the maximum pressure drop and wall shear stress.