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Numerical analysis of the flow through a corrugated tube with application to arterial prostheses

Published online by Cambridge University Press:  20 April 2006

C. N. Savvides
Affiliation:
Department of the Mechanics of Fluids, University of Manchester
J. H. Gerrard
Affiliation:
Department of the Mechanics of Fluids, University of Manchester

Abstract

Steady and oscillating axisymmetric laminar flows are determined by a finite-difference solution of the vorticity and continuity equations for an incompressible fluid contained in a straight concertina-shaped tube far from its ends. In steady flow the size of the wall corrugations is varied as well as the Reynolds number of the flow. In unsteady flow one tube geometry is studied, and the parameters varied are the Reynolds number, the ratio of the mean volume flow rate to its amplitude, and the frequency of oscillation. The analysis produces streamlines, particle paths and the pressure difference across a length of the tube. The resistance to the flow is determined in terms of an equivalent cylindrical tube diameter.

In steady flow the onset of flow separation and the growth of the separated region of flow is determined. The equivalent diameter is found to be principally a function of the product of Reynolds number and the non-dimensional pressure difference. This product depends on the height of the wall corrugations and less strongly on Reynolds number and the length of the corrugations. Resistance increases with increasing height of the corrugations. Comparison is made with other computational and experimental values of the pressure difference.

In unsteady flow the mean velocity to amplitude ratio has little effect except on the particle paths. The flow pattern is found to be governed by the Stokes number (radius × (2π/(kinematic viscosity × period))½) and the Reynolds number. There is a region of quasi-steady flow at the time of zero acceleration at maximum flow, but unsteady flow in between. The mixing produced by radial convection is restricted to the outer parts of the tube where the wall is corrugated. In oscillating flow the resistance relative to a cylindrical tube decreases as frequency and Reynolds number increase.

In the medical application of the work the concern is whether sustained stagnant regions occur in the corrugations and whether there is a large change in resistance relative to a cylindrical tube. This part of the investigation was made with an arterial waveform which contained six harmonics. It is found that there are no regions of stagnant fluid in the range of parameters considered. The difference between the variation with the flow parameters of the resistance of the corrugated tube and of a cylindrical tube was found not to be large.

Type
Research Article
Copyright
© 1984 Cambridge University Press

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References

Azzam, M. I. S. & Dullien, F. A. L. 1977 Flow in tubes with periodic step changes in diameter: a numerical solution. Chem. Engng Sci. 32, 1445.
Batra, V. K., Fulford, G. D. & Dullien, F. A. L. 1970 Laminar flow through periodically convergent-divergent tubes and channels Can. J. Chem. Engng 18, 622.Google Scholar
Butler, G. A. 1979 Blood flow in arteries with and without prosthetic inserts. Ph.D. thesis,. University of Manchester.
Caro, C. G., Fitzgerald, J. F. & Schroter, R. C. 1971 Atheroma and arterial shear. Proc. R. Soc. Lond. B 177, 109.Google Scholar
Deiber, J. A. & Schowalter, W. R. 1979 Flow through tubes with sinusoidal axial variations in diameter AIChE J. 25, 638.Google Scholar
Figliola, R. S. & Mueller, T. J. 1981 On the hemolytic and thrombogenic potential of occluder prosthetic heart valves from in vitro measurements. Trans. ASME K: J. Biomech. Engng 103, 83.Google Scholar
Fry, D. L. 1968 Acute vascular endothelial changes associated with increased blood velocity gradients Circulation Res. 22, 165.Google Scholar
Gerrard, J. H. 1971 The stability of unsteady axisymmetric incompressible pipe flow close to a piston J. Fluid Mech. 50, 625.Google Scholar
Gillani, N. V. & Swanson, W. M. 1976 Time dependent laminar incompressible flow through a spherical cavity J. Fluid Mech. 78, 99.Google Scholar
Lasalle, A. J., Brewster, D. C., Corson, J. D. & Darling, R. C. 1982 Femoropopliteal composite bypass grafts; current status Surgery 92, 36.Google Scholar
Macagno, E. O. & Hung, T. K. 1967 Computational and experimental study of a captive annular eddy J. Fluid Mech. 28, 43.Google Scholar
Mcdonald, D. A. 1974 Blood Flow in Arteries. Arnold.
Middleman, S. 1972 Transport Phenomena in the Cardivascular System. Wiley.
Mirolyubov, S. G. 1979 Pulsating flow of a Newtonian liquid through an axisymmetric tube with local enlargement. Izv. Akad. Nauk SSSR, Mekh. Zhid. i Gaza no. 6, 125.Google Scholar
Moffatt, H. K. 1964 Viscous and resistive eddies near a sharp corner J. Fluid Mech. 18, 1.Google Scholar
Pearson, C. E. 1965 A computational method for viscous flow problems J. Fluid Mech. 21, 611.Google Scholar
Roache, P. J. 1972 Computational Fluid Dynamics. Hermosa.
Smith, F. T. 1976 Flow through constricted or dilated pipes and channels: Parts I and II. Q. J. Mech. Appl. Maths 29, 343 and 365.Google Scholar
Sobey, I. J. 1980 On flow through furrowed channels. Part 1. Calculated flow patterns J. Fluid Mech. 96, 1.Google Scholar
Thoman, D. C. & Szewczyk, A. A. 1964 Time dependent viscous flow over a circular cylinder Phys. Fluids 12, II76.Google Scholar
Williams, G. P. 1969 Numerical integration of the three-dimensional Navier-Stokes equations for incompressible flow J. Fluid Mech. 37, 727.Google Scholar