Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand.
Compr Physiol. 2011 Jul;1(3):1135-57. doi: 10.1002/cphy.c100020.
Local characteristics of airflow and its global distribution in the lung are determined by interaction between resistance to flow through the airways and the compliance of the tissue, with tissue compliance dominating flow distribution in the healthy lung. Current understanding is that conceptualizing the airways of the lung as a system of smooth adjoined cylinders through which air traverses laminarly is insufficient for understanding flow and energy dissipation and is particularly poor for predicting physiologically realistic transport of particles by the airflow. With rapid advances in medical imaging, computer technologies, and computational techniques, computational fluid dynamics is now becoming a viable tool for providing detailed information on the mechanics of airflow in the human respiratory tract. Studies using such techniques have shown that the upper airway (specifically its development of a turbulent laryngeal jet in the trachea), airway geometry, branching and rotation angle, and the pattern of joining of successive bifurcations are important in determining airflow structures. It is now possible to compute airflow in physical domains that are anatomically accurate and subject specific, enabling comparisons among intersubjects, that among subjects of different ages, and that among different species.
气流的局部特征及其在肺部的全球分布是由通过气道的流动阻力与组织顺应性之间的相互作用决定的，在健康的肺部中，组织顺应性主导着气流的分布。目前的认识是，将肺部的气道概念化为一个平滑连接的圆柱体系统，空气在其中层流通过，对于理解流动和能量耗散来说是不够的，对于预测气流中颗粒的生理现实传输尤其差。随着医学成像、计算机技术和计算技术的快速发展，计算流体动力学现在正成为提供有关人体呼吸道气流力学详细信息的可行工具。使用此类技术的研究表明，上呼吸道（特别是其在气管中形成湍流的喉射流）、气道几何形状、分支和旋转角度以及连续分叉的连接方式对于确定气流结构很重要。现在可以在解剖上准确且针对特定个体的物理域中计算气流，从而可以在个体之间、不同年龄的个体之间以及不同物种之间进行比较。
