Transitional pulsatile flows with stenosis in a two-dimensional channel
نویسندگان
چکیده
Although blood flows are mostly laminar, transition to turbulence and flow separations observed at curved vessels, bifurcations, or constrictions. It is known that wall-shear stress plays an important role in the development of atherosclerosis as well arteriovenous grafts. In order help understand behavior separation post-stenotic flows, experimental study transitional pulsatile with stenosis was carried out using time-resolved particle image velocimetry a microelectromechanical systems sensor mean Reynolds number 1750 Womersley 6.15. At start cycle, strong shear layer develops from tip stenosis, increasing region. The throat always laminar due acceleration, which quickly becomes turbulent through shear-layer instability under adverse pressure gradient. same time, recirculation region appears over wall opposite moving downstream sync movement reattachment point. These behaviors two-dimensional channel very similar results obtained previously pipe flow. We also found pulsating during acceleration phase both 25% 50% cases steady flow, including location size regions. This because peak investigated. more dominant for compared wavelet spectra show greater broadening energy. With increase 75%, accelerating directed toward wall, creating jet. bifurcates result this, one upper other jet bottom wall. Low fluctuations two locations – immediately top (stenosis side) inside region, on (opposite side stenosis).
منابع مشابه
Direct Numerical Simulations of Transitional Pulsatile Flows in Stenotic Vessels
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ژورنال
عنوان ژورنال: Physics of Fluids
سال: 2021
ISSN: ['1527-2435', '1089-7666', '1070-6631']
DOI: https://doi.org/10.1063/5.0042753