Comparison of Theory and Experiment in Pulsatile Flow in Cat Lung

10.1114/1.107 ◽  
1998 ◽  
Vol 26 (5) ◽  
pp. 812-820 ◽  
Author(s):  
W. Huang ◽  
Y. Tian ◽  
J. Gao ◽  
R. T. Yen
2006 ◽  
Vol 291 (3) ◽  
pp. H1074-H1087 ◽  
Author(s):  
Yunlong Huo ◽  
Ghassan S. Kassab

The pulsatility of coronary circulation can be accurately simulated on the basis of the measured branching pattern, vascular geometry, and material properties of the coronary vasculature. A Womersley-type mathematical model is developed to analyze pulsatile blood flow in diastole in the absence of vessel tone in the entire coronary arterial tree on the basis of previously measured morphometric data. The model incorporates a constitutive equation of pressure and cross-section area relation based on our previous experimental data. The formulation enables the prediction of the impedance, the pressure distribution, and the pulsatile flow distribution throughout the entire coronary arterial tree. The model is validated by experimental measurements in six diastolic arrested, vasodilated porcine hearts. The agreement between theory and experiment is excellent. Furthermore, the present pulse wave results at low frequency agree very well with previously published steady-state model. Finally, the phase angle of flow is seen to decrease along the trunk of the major coronary artery and primary branches toward the capillary vessels. This study represents the first, most extensive validated analysis of Womersley-type pulse wave transmission in the entire coronary arterial tree down to the first segment of capillaries. The present model will serve to quantitatively test various hypotheses in the coronary circulation under pulsatile flow conditions.


1976 ◽  
Vol 98 (1) ◽  
pp. 27-32 ◽  
Author(s):  
L. C. Thomas ◽  
R. K. Shukla

Attention is focused in this study upon the development of a surface renewal-based analysis of transitional turbulent pulsatile flow and upon the experimental measurement of the instantaneous wall region turbulent periodicity. The resulting theoretical predictions and experimental measurements for periodicity provide a direct test of the validity of the model. The theory and experiment taken together provide further physical insight into the mechanism associated with this complex problem.


Author(s):  
Gertrude F. Rempfer

I became involved in electron optics in early 1945, when my husband Robert and I were hired by the Farrand Optical Company. My husband had a mathematics Ph.D.; my degree was in physics. My main responsibilities were connected with the development of an electrostatic electron microscope. Fortunately, my thesis research on thermionic and field emission, in the late 1930s under the direction of Professor Joseph E. Henderson at the University of Washington, provided a foundation for dealing with electron beams, high vacuum, and high voltage.At the Farrand Company my co-workers and I used an electron-optical bench to carry out an extensive series of tests on three-electrode electrostatic lenses, as a function of geometrical and voltage parameters. Our studies enabled us to select optimum designs for the lenses in the electron microscope. We early on discovered that, in general, electron lenses are not “thin” lenses, and that aberrations of focal point and aberrations of focal length are not the same. I found electron optics to be an intriguing blend of theory and experiment. A laboratory version of the electron microscope was built and tested, and a report was given at the December 1947 EMSA meeting. The micrograph in fig. 1 is one of several which were presented at the meeting. This micrograph also appeared on the cover of the January 1949 issue of Journal of Applied Physics. These were exciting times in electron microscopy; it seemed that almost everything that happened was new. Our opportunities to publish were limited to patents because Mr. Farrand envisaged a commercial instrument. Regrettably, a commercial version of our laboratory microscope was not produced.


1978 ◽  
Vol 39 (12) ◽  
pp. 1355-1363 ◽  
Author(s):  
L.G. Caron ◽  
M. Miljak ◽  
D. Jerome

2016 ◽  
Vol 64 (S 02) ◽  
Author(s):  
A. Salameh ◽  
L. Kuehne ◽  
M. Grassl ◽  
M. Gerdom ◽  
S. von Salisch ◽  
...  

1997 ◽  
Vol 37 (2) ◽  
pp. 225 ◽  
Author(s):  
Hye Won Chung ◽  
Myung Jin Chung ◽  
Jae Hyung Park ◽  
Jin Wook Chung ◽  
Dong Hyuk Lee ◽  
...  

1986 ◽  
Vol 150 (10) ◽  
pp. 321
Author(s):  
V.L. Dunin-Barkovskii

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