用于估算气道压降的非定常形式的伯努利方程。

The unsteady form of the Bernoulli equation for estimating pressure drop in the airways.

作者信息

Moslehi F, Ligas J R, Pisani M A, Epstein M A

机构信息

Department of Anesthesiology, University of Connecticut School of Medicine, Farmington 06032.

出版信息

Respir Physiol. 1989 Jun;76(3):319-26. doi: 10.1016/0034-5687(89)90072-8.

DOI:10.1016/0034-5687(89)90072-8

PMID:2749031

Abstract

Previous investigators have used the steady Bernoulli equation to correct the underestimation of alveolar pressure by airway pressure observed during unsteady flow conditions. Using a simple idealized geometry, we demonstrate a method of including the unsteady term of the Bernoulli equation. Our approach was to determine the axial velocity distribution from the wave equation and employ this solution with the unsteady Bernoulli equation. In addition, we estimate the importance of inertia and viscosity and show that these effects can be quantified by the Womersley number.

摘要

先前的研究人员使用稳定的伯努利方程来纠正非稳定流动条件下观察到的气道压力对肺泡压力的低估。通过一个简单的理想化几何结构，我们展示了一种纳入伯努利方程非稳定项的方法。我们的方法是从波动方程确定轴向速度分布，并将该解与非稳定伯努利方程一起使用。此外，我们估计了惯性和粘性的重要性，并表明这些效应可以通过沃默斯利数来量化。