Sertaç ÇADIRCI, Ufuk DEMİR, Semra Zülal BİROL, Levent TRABZON, Hasan GÜNEŞ

Mikrokanallarda cidar kayma gerilmesi ve basınç farkının sayısal olarak incelenmesi

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.

Anahtar Kelimeler:

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

Numerical investigation of wall shear stress and pressure difference in microchannels

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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