Chang H K, El Masry O A
Respir Physiol. 1982 Jul;49(1):75-95. doi: 10.1016/0034-5687(82)90104-9.
We measured detailed steady inspiratory and expiratory velocity profiles in a 3:1 scale model of the human central airways. The model was constructed out of acrylic plastic, mounted vertically, and connected to a specially designed steady-flow system. Laterally introduced hot-wire anemoneter probes were used to record axial velocities along 4 diameters at each of the 12 pre-drilled stations of measurement; the flow distribution among the five lobar bronchi was controlled by distally positioned linear resistors. Whether with a flat entrance profile or entering as a narrow jet, the inspiratory flow velocity profiles in the frontal plane showed a high degree of asymmetry in all branches, with peak velocities near the inner wall of the bifurcation. In the sagittal plane the velocity profiles were nearly symmetric, exhibiting a single peak near the center in the frontal plane and almost flat in the sagittal plane. Overall, the velocity profiles were more sensitive to airway geometry than to flow rate. The only site of flow separation was observed in the right upper lobar bronchus. The most evident modification of axial velocity profiles in a single branch was found in the left main bronchus during expiratory flow.
我们在一个人体中央气道的3:1比例模型中测量了详细的稳定吸气和呼气速度剖面。该模型由丙烯酸塑料制成，垂直安装，并连接到一个专门设计的稳流系统。横向引入的热线风速仪探头用于在12个预先钻孔的测量站中的每个站沿4个直径记录轴向速度；五个叶支气管之间的流量分布由位于远端的线性电阻器控制。无论是具有平坦的入口剖面还是以狭窄射流形式进入，额面内的吸气流速剖面在所有分支中都表现出高度不对称，峰值速度靠近分叉的内壁。在矢状面中，速度剖面几乎是对称的，在额面中心附近呈现单个峰值，在矢状面中几乎是平坦的。总体而言，速度剖面对气道几何形状比对流速更敏感。仅在右上叶支气管中观察到了气流分离的部位。在呼气过程中，在左主支气管中发现单个分支中轴向速度剖面的最明显变化。
