In vitro boundary layer studies of blood flow in branched tubes

Gutstein, William H.; Schneck, Daniel J.

doi:10.1016/s0368-1319(67)80056-5

Cited by 40 publications

(9 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At branches or bifurcations, boundary layer separation may occur on one wall, resulting in the formation of a standing vortex. This has been predicted theoretically (50) and has been observed in vitro (51,52) and in vivo (53). In this region, shear rates are low and stagnation occurs behind the vortex; here concentration polarization would be greatest.…”

Section: Discussionsupporting

confidence: 73%

Ultrafiltration of lipoproteins through a synthetic membrane

Colton¹,

Friedman²,

Wilson³

et al. 1972

J. Clin. Invest.

View full text Add to dashboard Cite

A B S T R A C T To investigate the interaction of lipoproteins with semipermeable membranes, solutions of low density lipoproteins (LDL), very low density lipoproteins (VLDL), mixtures of the two, and diluted, normal, and hyperlipidemic serum were ultrafiltered through a synthetic membrane (500 A nominal pore diameter) using a stirred laboratory ultrafiltration cell. The pressure dependence of ultrafiltrate flux showed that a concentrated layer of lipoproteins was built up at the membrane surface (concentration polarization) and that VLDL was more subject to polarization than LDL. This phenomenon controlled the observed lipoprotein transport behavior. Whereas true membrane rejection (the fraction of the solute on the membrane surface which does not pass through the membrane) was greater than 0.95 for both LDL and VLDL, observed solute rejection varied from nearly 0 to 1.0, depending upon experimental conditions.If concentration polarization occurs in the arterial system, these results suggest that lipoprotein transport into arterial wall may be influenced not only by arterial blood pressure and the properties of the arterial wall, but also by local hemodynamic conditions and by the relative as well as absolute magnitudes of LDL and VLDL concentration.

show abstract

Section: Discussionsupporting

confidence: 73%

Ultrafiltration of lipoproteins through a synthetic membrane

Colton¹,

Friedman²,

Wilson³

et al. 1972

J. Clin. Invest.

View full text Add to dashboard Cite

show abstract

“…In flow experiments the values used have not always been realistic. Davis [1963], Krovetz [1965] and Gutstein and Schneck [1967] all used an area ratio of 2. In the models illustrated by Attinger [1964], while the diameters of the branches and stems varied, the ratio was again close to a value of 2.…”

Section: Discussionmentioning

confidence: 99%

“…The possibility of flow separation at or rather immediately beyond the lateral angles of forks has been considered by several workers [Stehbens, 1960;Gutstein and Schneck, 1967]. Caro [1966] asserted that the area ratio would determine whether or not flow separation could occur at arterial forks and indicated that 1-2 has been regarded as the critical value above which flow separation is likely [Lighthill, 1972].…”

Section: Discussionmentioning

confidence: 99%

Flow in Glass Models of Arterial Bifurcations and Berry Aneurysms at Low Reynolds Numbers

Stehbens

1975

Exp Physiol

View full text Add to dashboard Cite

Using the dye injection technique, flow at low Reynolds numbers was studied in glass models which simulated arterial bifurcations of varying angles and had varying bluntness of the apex or crotch. Forks bearing small saccular evaginations simulating berry aneurysms were investigated similarly. At quite low Reynolds numbers in all the models small wave motion was observed at the forks. At higher Reynolds numbers and below the critical values for turbulence, larger vortices akin to a K'arman vortex street were shed from most of the forks. The disturbances were attributed to boundary layer separation and a jet-edge effect.

show abstract

“…More recent studies have shown that the area ratio of a typical arterial bifurcation is on the order of unity (4), and, indeed, that the area ratio of the aortic-iliac bifurcation is generally less than unity, even for nonatherosclerotic subjects (34). The results of earlier model studies (35)(36)(37)(38)(39), however, are all based on flow through branching geometries for which the outlet area was approximately equal to twice the inlet area for each branching configuration. The conclusions that are drawn in these studies with respect to conditions leading to transition (36,37), flow separation (38,39), and platelet deposition (35) are not necessarily applicable to flow in the arterial system.…”

Section: Gessner Flow Separation Hypothesesmentioning

confidence: 99%

Brief Reviews: Hemodynamic Theories of Atherogenesis

Gessner

1973

Circulation Research

View full text Add to dashboard Cite

In vitro boundary layer studies of blood flow in branched tubes

Cited by 40 publications

References 6 publications

Ultrafiltration of lipoproteins through a synthetic membrane

Ultrafiltration of lipoproteins through a synthetic membrane

Flow in Glass Models of Arterial Bifurcations and Berry Aneurysms at Low Reynolds Numbers

Brief Reviews: Hemodynamic Theories of Atherogenesis

Contact Info

Product

Resources

About