Document Detail

The dispersion of indicator flowing through simplified models of the circulation and its relevance to velocity profile in blood vessels.
MedLine Citation:
PMID:  5918057     Owner:  NLM     Status:  MEDLINE    
1. The distribution of velocity (velocity profile) was studied in water flowing through simple models of the circulation. Dye was injected and the distribution of velocity was assessed from indicator concentration-time curves recorded with a photomultiplier.2. Observations were made on straight and curved tubes and on a tube containing a short region with an elliptical cross-section. With steady flow, the rate was varied over the range 24-870 ml./min (Reynolds number 102-3690). Sinusoidal pulsations were imposed on the steady flow in some experiments.3. Bends gave rise to large secondary flows. These caused mixing across the flow and a marked reduction in the variation of velocity over the cross-section of the tube. The effect of bends on velocity distribution was maximal at a Reynolds number of ca. 1000. Similar, but far smaller, effects were seen in a region with an elliptical cross-section and when the flow was made pulsatile. Secondary motion due to bends was capable of preventing a heavier-than-water indicator ( 1.375) from settling out of the flow.4. The experimental findings suggest that there may be secondary flows in vascular beds. Under certain conditions, these would prevent the establishment of Poiseuille type laminar flow. The possible physiological importance of the findings is discussed.
C G Caro
Related Documents :
836357 - Inverse effect of chronically elevated blood flow on atherogenesis in miniature swine.
6465017 - Assessment of tricuspid regurgitation by pulsed doppler ultrasonography of the hepatic ...
8300887 - The relationship between the degradation of prostacyclin in blood and antiplatelet drug...
17930927 - Transport and aggregation of self-propelled particles in fluid flows.
3976897 - Fluid uptake in the renal papilla by vasa recta estimated by two methods simultaneously.
20369847 - Structural evolution of colloidal gels during constricted microchannel flow.
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  The Journal of physiology     Volume:  185     ISSN:  0022-3751     ISO Abbreviation:  J. Physiol. (Lond.)     Publication Date:  1966 Aug 
Date Detail:
Created Date:  1966-12-26     Completed Date:  1966-12-26     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  0266262     Medline TA:  J Physiol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  501-19     Citation Subset:  IM    
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Blood Circulation / physiology*
Blood Flow Velocity*
Coloring Agents / analysis
Models, Theoretical
Reg. No./Substance:
0/Coloring Agents; 7732-18-5/Water

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Interaction of cortex and superior colliculus in mediation of visually guided behavior in the cat.
Next Document:  S-potentials from colour units in the retina of fish (Cyprinidae).