scholarly journals Animated versus static views of steady flow patterns

2016 ◽  
Author(s):  
Colin Ware ◽  
Daniel Bolan ◽  
Ricky Miller ◽  
David H. Rogers ◽  
James P. Ahrens
Keyword(s):  
Steady Flow ◽  
Flow Patterns

Analysis of Fully Developed Unsteady Viscous Flow in a Curved Elastic Tube Model to Provide Fluid Mechanical Data for Some Circulatory Path-Physiological Situations and Assist Devices

1979 ◽  
Vol 101 (2) ◽  
pp. 114-123 ◽  
Author(s):  
K. B. Chandran ◽  
R. R. Hosey ◽  
D. N. Ghista ◽  
V. W. Vayo
Keyword(s):  
Shear Stress ◽  
Unsteady Flow ◽  
Steady Flow ◽  
Pulsatile Flow ◽  
Flow Patterns ◽  
Elastic Tube ◽  
Flow Component ◽  
Flow Response ◽  
Elastic Tubes ◽  
Flow Components

The unsteady and steady flow components of pulsatile flow response, to an experimentally monitored representative pressure pulse, are computed to provide fluid mechanical data for the etiology of arteriosclerosis at arterial curvature sites and for the design analysis of some extracorporeal dialysis and oxygenatory systems. The unsteady flow component of pulsatile flow in curved elastic tubes is simulated by the superposition of the first six Fourier components of a derived oscillatory flow solution of a viscous, incompressible fluid through an elastic tube of small curvature. The computer flow patterns, wall shear stress and hoop and axial stresses in the wall, due to unsteady and steady flow components of pulsatile flow response, are compared and their implications are discussed. The results show that the unsteady component yields shear stress of an order of magnitude greater than the steady flow, but the steady flow component has a greater variation in the shear stress distribution over a cross section. The steady and unsteady flow patterns are presented for several values of the tube diameters and curvature parameters typical of major arteries in the human circulatory system. The flow pattern and the stress variations could also prove useful in the design of extracorporeal systems such as dialysis machines and oxygenators.

scholarly journals Flow Patterns in the Dog Descending Aorta under a Steady Flow Condition Simulating Mid-Systole

2004 ◽  
Vol 47 (4) ◽  
pp. 1000-1009 ◽  
Author(s):  
Shunsuke ENDO ◽  
Harry Leonardo GOLDSMITH ◽  
Takeshi KARINO
Keyword(s):  
Steady Flow ◽  
Flow Condition ◽  
Flow Patterns ◽  
Descending Aorta ◽  
Steady Flow Condition

Steady flow patterns in a bubble column with vertical inserts

1993 ◽  
Vol 27 (3) ◽  
pp. 345-352
Author(s):  
V. L. Zelenko ◽  
V. P. Myasnikov
Keyword(s):  
Steady Flow ◽  
Bubble Column ◽  
Flow Patterns

Comparison of Steady and Pulsatile Flow Near the Ventral and Dorsal Walls of Casts of Human Aortic Bifurcations

1984 ◽  
Vol 106 (1) ◽  
pp. 79-82 ◽  
Author(s):  
O. J. Deters ◽  
F. F. Mark ◽  
C. B. Bargeron ◽  
M. H. Friedman ◽  
G. M. Hutchins
Keyword(s):  
Secondary Flow ◽  
Steady Flow ◽  
Pulsatile Flow ◽  
Flow Direction ◽  
Flow Patterns ◽  
Laser Doppler Anemometer ◽  
Common Features ◽  
Fluid Velocities ◽  
Pulsatile Flows ◽  
The Common

Steady and pulsatile flows were passed through casts of human aortic bifurcations and, by means of a laser Doppler anemometer, fluid velocities were measured at selected sites near the ventral and dorsal walls. At these sites, in the vicinity of the bifurcation, the influence of secondary flow is significant and therefore an appreciation of the phasic variation of secondary flow patterns is important. Results are presented comparing the flow direction in both steady and pulsatile flow at sites in three casts. The common features of the flow at these sites were the persistence of the flow direction during the accelerating and decelerating phases of the pulsatile cycle, and the consistently smaller angle (measured from the inlet centerline) of the pulsatile flow direction as compared to the angle of the flow direction in steady flow.

Numerical Analysis of Design and Off-Design Performance of High Specific Speed Mixed Flow Pumps

2011 ◽  
Author(s):  
Yumiko Sekino ◽  
Yoichi Tanabe
Keyword(s):  
Steady Flow ◽  
Periodic Boundary ◽  
Flow Analysis ◽  
Flow Patterns ◽  
Design Flow ◽  
Cfd Analysis ◽  
Mixed Flow ◽  
Blade Passage ◽  
Specific Speed ◽  
Flow Pump

In most cases of high specific speed mixed flow pump applications, it is necessary to control off-design performance such as shutoff power/head and unstable characteristic as well as design point performance. The authors have been working on multi-objective optimization strategy of mixed flow pump design considering off-deign performance by means of Computational Fluid Dynamics (CFD). In the design optimization process, it was found that the steady CFD analysis using one pitch blade passage adopting periodic boundary condition could be used for relative comparison of the important performance characteristics such as the level of efficiency, the shutoff performance and the stall characteristics of different designs. However, the steady CFD analysis with one pitch blade passage showed that absolute values of head and shaft power were estimated lower than those of the experimental results especially in the partial capacity range. In order to improve the accuracy of CFD results it should be necessary to use full pitch model. In this paper, the evaluation results of three CFD approaches on the capability of the performance prediction of the mixed flow pumps will be shown. The approaches evaluated are steady flow analysis with one pitch blade passage using periodic boundary conditions, full pitch steady flow analysis and unsteady flow analysis. It was found from the evaluation results that the full pitch steady flow analysis showed the same tendency as one pitch analysis and the unsteady CFD provided higher accuracy of the shutoff head. However, the steady analysis should still be useful to reduce the high computational cost and the amount of time. Meanwhile the unsteady analysis clarifies the details of the off-design flow patterns. The effects of the turbulence models and the details of the off-design flow patterns were also discussed in this paper.

Flow patterns in dog aortic arch under a steady flow condition simulating mid-systole

1996 ◽  
Vol 11 (4) ◽  
pp. 180-191 ◽  
Author(s):  
Shunsuke Endo ◽  
Yasunori Sohara ◽  
Takeshi Karino
Keyword(s):  
Aortic Arch ◽  
Steady Flow ◽  
Flow Condition ◽  
Flow Patterns ◽  
Steady Flow Condition
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