Pore-Scale Modeling of Non-Newtonian Shear-Thinning Fluids in Blood Oxygenator Design.
Pore-Scale Modeling of Non-Newtonian Shear-Thinning Fluids in Blood Oxygenator Design.
复制标题
血液氧合器设计中非牛顿剪切稀化流体的孔隙尺度建模。
DOI：
10.1115/1.4032801
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
J. Sienz
中科院分区：
文献类型：
--
作者：
Kenny W. Q. Low;R. Van Loon;S. Rolland;J. Sienz
本文回顾并进一步发展了用于血液氧合器中正交各向异性纤维束蠕动流动的孔尺度计算流动建模技术。多孔模型采用均匀化方法对纤维束进行建模，大大降低了几何复杂性。这大大简化了网格划分，并可以避免大量耗时的模拟。渗透率和孔隙度之间的解析关系存在于通过规则排列的纤维的牛顿流中，并且通常通过在流动动量方程中引入达西粘性项而用于宏观多孔模型中。在这个程度上，验证分析牛顿渗透率-孔隙度关系已进行了平行和横向流动通过正方形和交错排列的纤维。然后使用类似的程序来确定非牛顿血液的渗透率-孔隙率关系。结果表明，通过最小二乘法拟合，将多孔介质粘度分解为常数项和方向表达式，建立广义Darcy方程，可以模拟多孔介质中非牛顿剪切稀化流体。这个概念，然后研究各种非牛顿血液粘度模型。所提出的方法进行了两种不同的多孔模型的方法，均质和非均质，并对高保真模型进行了验证。非均质多孔模型方法的结果改善了压力和速度分布，突出了壁面效应的重要性。
This paper reviews and further develops pore-scale computational flow modeling techniques used for creeping flow through orthotropic fiber bundles used in blood oxygenators. Porous model significantly reduces geometrical complexity by taking a homogenization approach to model the fiber bundles. This significantly simplifies meshing and can avoid large time-consuming simulations. Analytical relationships between permeability and porosity exist for Newtonian flow through regular arrangements of fibers and are commonly used in macroscale porous models by introducing a Darcy viscous term in the flow momentum equations. To this extent, verification of analytical Newtonian permeability-porosity relationships has been conducted for parallel and transverse flow through square and staggered arrangements of fibers. Similar procedures are then used to determine the permeability-porosity relationship for non-Newtonian blood. The results demonstrate that modeling non-Newtonian shear-thinning fluids in porous media can be performed via a generalized Darcy equation with a porous medium viscosity decomposed into a constant term and a directional expression through least squares fitting. This concept is then investigated for various non-Newtonian blood viscosity models. The proposed methodology is conducted with two different porous model approaches, homogeneous and heterogeneous, and validated against a high-fidelity model. The results of the heterogeneous porous model approach yield improved pressure and velocity distribution which highlights the importance of wall effects.
影响因子：
3.4
作者：
Fedosov, Dmitry A.;Caswell, Bruce;Karniadakis, George Em
通讯作者：
Karniadakis, George Em
影响因子：
3.5
作者：
Fedosov, Dmitry A.;Noguchi, Hiroshi;Gompper, Gerhard
通讯作者：
Gompper, Gerhard