Microscopic Flows and Macroscopic Flows Visualization and Measurement of Macro- and Microscopic Flows in In-Vitro Models

• Published in: Journal of Japan Society of Fluid Mechanics Vol. 25; no. 1; pp. 5 - 12
• Main Authors: Oshima Marie, KINOSHITA Haruyuki, BANDO Yoshinori
• Format: Journal Article
• Language: Japanese
• Published: The Japan Society of Fluid Mechanics 2006; 社団法人 日本流体力学会
• Subjects: Bio-Fluid Dynamics; Confocal Micro PIV; In Vitro Model; Micro Fluidics; Stereoscopic PIV
• ISSN: 0286-3154; 2185-4912
• DOI: 10.11426/nagare1982.25.5

The physical phenomena of blood flow vary depending on a size of blood vessel. If blood flows in a relatively large artery, it can be assumed to be Newtonian and pulsatile flow. On the other hand, if blood flows in a small artery, non-Newtonian effects become apparent. The authors have engaged in cerebral vascular flow experimentally and numerically. This paper particularly focuses on in vitro experiments for blood flow in two different types of scales using PIV measurements. The first example is stereoscopic PIV measurement of blood flow in the modeled cerebral aneurysm. The flow inside an aneurysm becomes complex due to complicated vascular geometry and pulsatile motion. In this study, a new calibration technique has been developed for stereoscopic PIV measurement of flow in complex geometry. The experiment is conducted to investigate hemodynamic characteristics in an in-vitro aneurysm model, whose geometry is constructed from medical images. The other example is confocal micro PIV measurement of the internal flow of a micro-sized droplet in a micro channel, which emulates flow in a small artery such as an arteriole. The paper will discuss both results and the significance of PIV measurement technique in visualization and measurement of bio-fluid. 血液は血漿成分および赤血球などの有形成分から構成されている. このため, 血液の流れる上血管径のスケールにより, 異なった流れの挙動を示す. 動脈を流れる血液は一般に拍動流でニュートン流体とみなすことができる.一方, 約100μm以下の細動脈では定常の層流だが, 非ニュートン流体となり赤血球の変形挙動を考慮する必要がある. そこで, 本研究では可視視化計測を行なう際に, 各スケールにおける流れの物理に応じたPIV手法の開発を行なった. そして, 血管を模擬したin vitroモデル内のマクロな流れとマイクロな流れに適用し, 各手法の妥当性を検証した.