Stergiopulos N, Tardy Y, Meister J J
Biomedical Engineering Laboratory, Swiss Federal Institute of Technology, Ecublens.
J Biomech. 1993 Feb;26(2):201-9. doi: 10.1016/0021-9290(93)90049-k.
A new method for the separation of forward and backward running waves in elastic conduits, with possible extension to the arterial system, has been developed. The mathematical model is based on the one-dimensional flow equations which allow the treatment of non-periodic or transient pressure and flow pulses. The method is fully nonlinear, i.e. no linearizing assumptions are made. The method includes the effects of convective acceleration and pressure-dependent vessel compliance. A first approximation for the fluid friction at the wall is also included. The application of the method requires the knowledge of the elastic properties, the instantaneous pressure and flow, as well as the instantaneous spatial derivatives of pressure and flow. Analysis of simulated data shows good results and suggests that the proposed method, unlike previous quasi-nonlinear and frequency domain methods, can be applied to strongly nonlinear and/or nonperiodic flows. The method predicts that if a linear analysis is applied to a nonlinear system errors arise.
已经开发出一种用于分离弹性管道中向前和向后行波的新方法，该方法可能扩展到动脉系统。数学模型基于一维流动方程，该方程允许处理非周期性或瞬态压力和流量脉冲。该方法是完全非线性的，即不做线性化假设。该方法包括对流加速度和压力依赖性血管顺应性的影响。还包括壁面流体摩擦的一阶近似。该方法的应用需要了解弹性特性、瞬时压力和流量，以及压力和流量的瞬时空间导数。对模拟数据的分析显示出良好的结果，并表明所提出的方法与以前的准非线性和频域方法不同，可以应用于强非线性和/或非周期性流动。该方法预测，如果对非线性系统应用线性分析，将会产生误差。
