摘要：目的 研究狭窄气道重建及不同呼吸状态下空气流场对气道壁面的影响。方法 运用Mimics建立了人体气道的三维模型，利用计算流体力学（CFD）对气道内的流场进行了仿真，分析并比较不同呼吸状态下气管内壁压力及其气流的分布状态。结果 在不同呼吸状态下，气管内壁压强数值在主气管内壁相对均匀，但在支气管狭窄段的气流入口处出现明显下降，在最狭窄的区域附近达到负压。气流速度从气管管道中心向边界层递减，流速在狭窄处达到最大值。气流穿过狭窄区域后产生涡流，且入口流速越大，正压和负压压强数值越大，狭窄处压降越明显，涡流现象越明显。结论 气道狭窄区域因负压造成继续收缩，会导致病人呼吸困难，而涡流会使气管壁受到气动剪切应力的影响可能损伤气道壁粘膜，因此了解气道内的压强分布及流速分布情况，可为气道狭窄的临床诊治提供参考依据。
Abstract：Objective The reconstruction of narrow airways and effects of air flow field on the airway wall under different breathing conditions were studied. Methods A three-dimensional model of human airway is established by using Mimics, and the flow field in the airway is simulated by computational fluid dynamics (CFD). The inner wall pressure and the distribution of airflow are analyzed and compared under different breathing states. Results Under different breathing conditions, the pressure value of endotracheal wall is relatively uniform in the endotracheal wall, but decreases significantly in the air inlet of the bronchial stenosis segment, and reaches negative pressure near the narrowest area. The airflow velocity decreases from the center of the pipe to the boundary layer, and the velocity reaches the maximum at the narrow area. Vortex is generated when airflow passes through the narrow area, and the larger the inlet flow velocity is, the larger the positive pressure and negative pressure values are, the more obvious the pressure drop at the narrow area is, and the more obvious the vortex phenomenon is. Conclusion The constriction of the airway stenosis area caused by negative pressure will lead to the patient's dyspnea, and the eddy current will cause the airway wall to be affected by the aerodynamic shear stress and may damage the airway wall mucosa. Therefore, the understanding of the pressure distribution and velocity distribution in the airway can provide a reference for the clinical diagnosis and treatment of airway stenosis.