Woo Y R, Yoganathan A P
Life Support Syst. 1986 Jan-Mar;4(1):47-62.
The measurements of velocity and turbulent shear stress in the immediate vicinity of prosthetic heart valves play a vital role in their design and evaluation. In the past, hot-wire/film and one-component laser Doppler anemometer (LDA) systems have been used extensively. Hot-wire/film anemometers, however, have some serious disadvantages, such as not being able to measure the directionality of the flow, disturbing the flow field with the probe, and requiring frequent calibration. One-component LDA systems do not have these problems, but they cannot measure turbulent shear stresses directly. Since these measurements are essential, and are not available in the open literature, a two-component LDA system was assembled to measure velocity and turbulent shear stress fields under pulsatile flow conditions. The experimental methodology used to create an in vitro data base of velocity and turbulent shear stress fields in the immediate vicinity of various designs of prosthetic heart valve in current clinical use is also discussed in this paper.
人工心脏瓣膜紧邻区域的速度和湍流剪应力测量在其设计和评估中起着至关重要的作用。过去，热线/热膜和单分量激光多普勒测速仪（LDA）系统被广泛使用。然而，热线/热膜风速仪存在一些严重缺点，比如无法测量流动方向、探头会干扰流场以及需要频繁校准。单分量LDA系统不存在这些问题，但它们无法直接测量湍流剪应力。由于这些测量至关重要且公开文献中没有相关内容，因此组装了一个双分量LDA系统来测量脉动流条件下的速度和湍流剪应力场。本文还讨论了用于创建当前临床使用的各种人工心脏瓣膜设计紧邻区域速度和湍流剪应力场体外数据库的实验方法。
