Study on gas/solid flow in an obstructed pulmonary airway with transient flow based on CFD-DPM approach
Study on gas/solid flow in an obstructed pulmonary airway with transient flow based on CFD-DPM approach
复制标题
基于CFD-DPM方法的瞬态流阻塞肺气道内气体/固体流动研究
DOI：
10.1016/j.powtec.2011.10.034
复制
发表时间：
2012-02-01
影响因子：
5.2
通讯作者：
Zhou, Xianguang
中科院分区：
文献类型：
--
作者：
Chen, Xiaole;Zhong, Wenqi;Zhou, Xianguang
建立了一个全面的三维数值模型，用于研究慢性阻塞性肺疾病（COPD）患者气道内的气固两相流动特性。气相采用层流计算流体动力学（CFD）模型，颗粒相采用离散相模型（CFD）模型。通过实验验证了三代气道内气固两相流动特性的计算结果。在此基础上，对有障碍物的四代气固两相流模型进行了数值模拟。比较了真实的吸入条件下，阻塞管和相邻代的气流流型和流量沿瞬态吸入时间序列的沿着变化规律，以及阻塞管和相邻代的颗粒沉积模式和效率，并与稳态进气结果进行了比较。研究发现，由于不稳定吸入的停滞区和回流区的发展，阻塞物及其下游各代的空气流速降低。与稳态进气相比，沉积区增大，沉积区变得更加分散。二次流可能有助于颗粒沉积在真实的吸入的发炎气道中。收缩管的沉积效率结果表明，瞬态吸气条件可能比稳态进气条件更适合于COPD或类似阻塞气道模拟。(C)2011 Elsevier B.V.保留所有权利。
A comprehensive three-dimensional numerical model was developed to study the gas/solid flow behaviors in a pulmonary airway affected by chronic obstructive pulmonary disease (COPD), a high morbidity lung disease and the patients of which suffer from respiratory difficulty caused by narrowed airway. The gas phase was modeled with laminar computational fluid dynamics (CFD) model and the particle phase was modeled with discrete phase model (DPM). Computational gas-solid flow behaviors in a three-generation airway were validated with experiment. After that gas/solid flow characteristics in an obstructed four-generation model were investigated by simulations. The air flow patterns and flow rates changing along the time series of transient inhalation and particle deposition patterns and efficiencies of the obstructed tube and adjacent generations under real inhalation condition were compared with the steady inlet results. It is found that air flow rates of the obstruction and its downstream generations reduce due to the stagnation and recirculation zones development with unsteady inhalation. Deposition area could enlarge and become more scattered than steady inlet. Secondary flow may contribute to the particle deposition in the inflamed airway for real inhalation. The deposition efficiency outcomes of the constricted tube indicate that transient inhalation condition may be more appropriate for COPD or similar obstructed airway simulation than steady inlet condition. (C) 2011 Elsevier B.V. All rights reserved.