Flow through collapsible tubes at high Reynolds numbers.
نویسندگان
چکیده
The pressure-flow relationships of collapsible tubes were studied utilizing the Starling resistor model. Reynolds numbers much higher than previously reported were used to simulate high cardiac output states. Alterations which occur in vivo, including longitudinal tension, stretch, tubing diameter, length, and outflow resistance were also simulated and systematically investigated. The pressure-flow curves showed an initial rising phase, a plateau phase, as well as a late-rising phase which has not been reported previously. Self-induced oscillations occurred during the plateau phase and persisted throughout the late-rising phase. These perturbations were markedly increased by longitudinal tension and stretch, but were attenuated by increased diameter, length, and outflow pressure. These instabilities may prove to be an explanation for the "venous hum."
منابع مشابه
Flow through collapsible tubes at low Reynolds numbers. Applicability of the waterfall model.
The applicability of the waterfall model was tested using the Starling resistor and different viscosities of fluids to vary the Reynolds number. The waterfall model proved adequate to describe flow in the Starling resistor model only at very low Reynolds numbers (Reynolds number less than 1). Blood flow characterized by such low Reynolds numbers occurs only in the microvasculature. Thus, it is ...
متن کاملLETTERS TO THE EDITOR Comments on Flow through Collapsible Tubes at Low Reynolds Numbers
In a recent paper by Lyon et al. (Flow through Collapsible Tubes at Low Reynolds Numbers. Circ Res 47: 68-73, 1980), the authors contend that waterfall models adequately predict flow through a Starling resistor only for Reynolds numbers <1. Their basic conclusion was that caution should be used when applying waterfall models to the mammalian circulatory system since Reynolds numbers are usually...
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عنوان ژورنال:
- Circulation research
دوره 49 4 شماره
صفحات -
تاریخ انتشار 1981