Mikrokanallarda cidar kayma gerilmesi ve basınç farkının sayısal olarak incelenmesi

Year 2018, Volume: 24 Issue: 1, 19 - 24, 27.02.2018

Sertaç Çadırcı , Ufuk Demir Semra Zülal Birol Levent Trabzon Hasan Güneş

Abstract

Bu
çalışmada farklı geometrideki mikrokanallar içerisinde saf su akışı için elde
edilen cidar kayma gerilmesi ve basınç farkı değerleri sayısal olarak elde
edilmiştir. Çalışma, benzer bir laboratuvar ortamında farklı debilerde endotel
ve immun sistem hücreleri üzerinde meydana gelebilecek farklı fiziksel etkileri
ve bu hücrelerin davranışlarını inceleyebilmek için bir ön çalışma
niteliğindedir. Belirlenen debi aralığında, endotel hücrelerinin ve monosit
hücrelerinin in-vivo’da fizyolojik olarak maruz kaldıkları ya da
kalabilecekleri alt ve üst cidar kayma gerilmesi değerleri sayısal olarak
tahmin edilmeye çalışılmıştır. Bu kapsamda; farklı genişleme oranlarına sahip
ani genişlemeli mikro- kanallar, bir cidarı kaviteli ve simetrik kıvrımlı mikrokanal
olarak adlandırılan üç değişik konfigürasyonda ve farklı hacimsel debi değerlerinde
analizler yapılarak, mikrokanal alt cidarlarında meydana gelen kayma gerilmesi
değerleri ve kanal girişi ile çıkışı arasında oluşan basınç farkı değerleri
sayısal olarak elde edilmiştir.

Keywords

Mikrokanal akışı, Hesaplamalı Akışkanlar Dinamiği (HAD), Mekano-biyolojik davranış, Cidar kayma gerilmesi

Numerical investigation of wall shear stress and pressure difference in microchannels

Abstract

In
this study, wall shear stress and pressure difference values for a pure water
flow in various microchannel configurations are obtained numerically. Through
simulations, physical effects of various flow rates on endothelium and immune
system cells are predicted and case studies are carried out to investigate the
behavior of such cells under similar laboratory conditions. In-vivo
physiological behavior of endothelium and monocyte cells under real conditions
can be predicted by pressure differences and wall shear stresses calculated for
various flowrates. In this concept, various microchannel configurations such as
sudden expanding microchannels with different expansion ratios, microchannels
with cavities on one side and symmetrically curved microchannels are designed
and CFD simulations are carried out to obtain computational values of the
pressure drops between the inlet and outlet of the microchannels as well as
wall shear stress distributions on the bottom walls of the configurations. 

Keywords

Microchannel flows, Computational Fluid Dynamics (CFD), Mechano-biological behavior, Wall shear stress

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