Wall Shear-Rate Estimation Within the 50cc Penn State Artificial Heart Using Particle Image Velocimetry

2004 ◽  
Vol 126 (4) ◽  
pp. 430-437 ◽  
Author(s):  
Pramote Hochareon ◽  
Keefe B. Manning ◽  
Arnold A. Fontaine ◽  
John M. Tarbell ◽  
Steven Deutsch
Keyword(s):  
Particle Image Velocimetry ◽  
Shear Rate ◽  
Artificial Heart ◽  
Particle Image ◽  
Design Procedure ◽  
Interrogation Window ◽  
Wall Shear Rate ◽  
Image Velocimetry ◽  
Penn State ◽  
Wall Shear

Particle image velocimetry (PIV) has been gaining acceptance as a routine tool to evaluate the flow fields associated with fluid mechanical devices. We have developed algorithms to investigate the wall shear-rates within the 50cc Penn State artificial heart using low magnification, conventional particle image velocimetry (PIV). Wall shear has been implicated in clot formation, a major post-implant problem with artificial hearts. To address the issues of wall scattering and incomplete measurement volumes, associated with near wall measurements, we have introduced a zero masking and a fluid centroid shifting technique. Simulations using different velocity fields were conducted with the techniques to assess their viability. Subsequently, the techniques were applied to the experimental data collected. The results indicate that the size of the interrogation region should be chosen to be as small as possible to maximize resolution while large enough to ensure an adequate number of particles per region. In the current study, a 16×16 interrogation window performed well with good spatial resolution and particle density for the estimation of wall shear rate. The techniques developed with PIV allow wall shear-rate estimates to be obtained from a large number of sites at one time. Because a planar image of a flow field can be determined relatively rapidly, PIV may prove useful in any preliminary design procedure.

Fluid Dynamic Analysis of the 50 cc Penn State Artificial Heart Under Physiological Operating Conditions Using Particle Image Velocimetry

2004 ◽  
Vol 126 (5) ◽  
pp. 585-593 ◽  
Author(s):  
Pramote Hochareon ◽  
Keefe B. Manning ◽  
Arnold A. Fontaine ◽  
John M. Tarbell ◽  
Steven Deutsch
Keyword(s):  
Particle Image Velocimetry ◽  
Artificial Heart ◽  
Particle Image ◽  
Flow Fields ◽  
Design Tool ◽  
Operating Conditions ◽  
Shear Rates ◽  
Heart Chamber ◽  
Image Velocimetry ◽  
Penn State

In order to bridge the gap of existing artificial heart technology to the diverse needs of the patient population, we have been investigating the viability of a scaled-down design of the current 70 cc Penn State artificial heart. The issues of clot formation and hemolysis may become magnified within a 50 cc chamber compared to the existing 70 cc one. Particle image velocimetry (PIV) was employed to map the entire 50 cc Penn State artificial heart chamber. Flow fields constructed from PIV data indicate a rotational flow pattern that provides washout during diastole. In addition, shear rate maps were constructed for the inner walls of the heart chamber. The lateral walls of the mitral and aortic ports experience high shear rates while the upper and bottom walls undergo low shear rates, with sufficiently long exposure times to potentially induce platelet activation or thrombus formation. In this study, we have demonstrated that PIV may adequately map the flow fields accurately in a reasonable amount of time. Therefore, the potential exists of employing PIV as a design tool.

Two-dimensional shear rate field and flow structures of a pseudoplastic fluid in a stirred tank using particle image velocimetry

2021 ◽  
pp. 117198
Author(s):  
Jenniffer S. Ayala ◽  
Helder L. de Moura ◽  
Rodrigo de L. Amaral ◽  
Francisco de A. Oliveira Júnior ◽  
José R. Nunhez ◽  
...  
Keyword(s):  
Particle Image Velocimetry ◽  
Shear Rate ◽  
Particle Image ◽  
Stirred Tank ◽  
Flow Structures ◽  
Two Dimensional ◽  
Pseudoplastic Fluid ◽  
Image Velocimetry

Particle image velocimetry measurements of three proximal anastomosis models under a pulsatile flow condition

2008 ◽  
Vol 222 (3) ◽  
pp. 249-263 ◽  
Author(s):  
L P Chua ◽  
W-F Ji ◽  
C M Yu ◽  
T-M Zhou ◽  
Y S Tan
Keyword(s):  
Shear Stress ◽  
Particle Image Velocimetry ◽  
Wall Shear Stress ◽  
Flow Condition ◽  
Particle Image ◽  
Proximal Anastomosis ◽  
Recirculation Flow ◽  
Image Velocimetry ◽  
Anastomotic Angle ◽  
Wall Shear

This study was designed to examine the effects of the anastomotic angle on the flow and haemodynamic parameter distribution patterns of the proximal anastomoses, with emphasis on identifying site-specific haemodynamic features that could reasonably be expected to trigger the initiation and further development of anastomotic intimal hyperplasia. Particle image velocimetry measurements were carried out with three simplified glass proximal models under a physiological flow condition. The results revealed that the disturbed flow and the induced shear stress patterns including low recirculation flow, stagnation point, high wall shear stress, high temporal wall shear stress gradient, low time-averaged wall shear stress (TAWSS), and high oscillating shear index (OSI) occurred around the anastomotic joints and the flow field at proximal anastomosis was strongly affected by the anastomotic angle. Among the three models investigated, the 45° backward anastomosis is found to have a smaller low-recirculation-flow region along the graft inner wall, non-stationary stagnation, and separation points, a higher TAWSS and smaller high-OSI low-TAWSS and low-OSI high-TAWSS regions.

Arterial Wall Shear Stress Measurement In Vivo Using Echo Particle Image Velocimetry (Echo PIV)

2011 ◽  
Vol 43 (Suppl 1) ◽  
pp. 743-744
Author(s):  
Kunihiko Aizawa ◽  
Phillip E. Gates ◽  
W David Strain ◽  
Oliver E. Gosling ◽  
Luciano Mazzaro ◽  
...  
Keyword(s):  
Shear Stress ◽  
Particle Image Velocimetry ◽  
Wall Shear Stress ◽  
Arterial Wall ◽  
Particle Image ◽  
Stress Measurement ◽  
Image Velocimetry ◽  
Wall Shear ◽  
Wall Shear Stress Measurement
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