Abstract：
:Vortex-ring production was studied in axisymmetric elastomeric ventricles designed to stimulate flow in a cardiovascular assist device. A flow visualization technique was used to investigate the effects of reducing the inlet diameter and predilating the ventricle on vortex travel in two ventricles of different shape and size. In most cases, vortex rings formed during the filling phase. They were bounded by the incoming jet of fluid and the ventricular wall. The velocity of their centres during the filling period was proportional to the inflow velocity. During filling, vortex velocity was substantially independent of the shape and diameter of the two ventricles studied. It was dependent mainly on orifice diameter: a narrower inlet led to greater inflow velocities and proportionately greater vortex velocities. At the end of the filling phase, each vortex increased in size to occupy the full radial extent of the ventricle. This process was associated with a decrease in the axial velocity and strength of the vortex. At low flow rates, these losses resulted in the arrest of the vortex at end filling. Vortex motion in ventricles is particularly important in the design of a cardiovascular device such as the skeletal muscle ventricle (SMV), where small ejection fractions may leave blood at the apex of the ventricle relatively undisturbed. It is suggested that inlet diameter could be selected to favour the formation and travel of vortices, with a resultant reduction in apical residence time and hence a reduced risk of thrombus formation.
journal_name
J Biomechjournal_title
Journal of biomechanicsauthors
Shortland AP,Black RA,Jarvis JC,Henry FS,Iudicello F,Collins MW,Salmons Sdoi
10.1016/0021-9290(95)00065-8subject
Has Abstractpub_date
1996-04-01 00:00:00pages
503-11issue
4eissn
0021-9290issn
1873-2380pii
0021-9290(95)00065-8journal_volume
29pub_type
杂志文章abstract：:Joint distraction and mobilization with a hinged external fixator preserves elbow stability and mobility. However, the alignment of both elbow and fixator hinges was the initial prerequisite of the arthrodiatasis technique. The main goal of this study was to numerically evaluate the kinematic influence of the device, ...
journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/0021-9290(95)00108-5
更新日期：1996-05-01 00:00:00
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journal_title：Journal of biomechanics
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更新日期：2014-02-07 00:00:00
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pub_type： 杂志文章
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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更新日期：2012-06-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
doi：10.1016/j.jbiomech.2013.04.005
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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更新日期：1991-01-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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更新日期：2000-05-01 00:00:00
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journal_title：Journal of biomechanics
pub_type： 杂志文章
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更新日期：2012-05-11 00:00:00
