Numerical Modeling of the Movement of Self-Propelled Microorganisms in Newtonian Fluid

Öz

The movement of micro-organisms is important both in understanding their biological behavior and in micro-robot design. The micro swimmer is often displaced by squirming motion at very low speeds in stationary fluid, a flow dominated by viscosity due to the low Reynolds number. The squirming movement differentiates the effect of the drag forces of the swimmer. Time-dependent periodic squirming motion for forward, reverse and neutral mode movements is modeled by ANSYS® software. The results are presented as streamlines, velocity isocurves, and wall shear force, vorticity, and drag coefficient variation at the swimmer wall for a full period after steady state is reached. It has been shown that the swimming efficiency of a squirming swimmer is dependent on both the Reynolds number and the swimmer's mode.

Anahtar Kelimeler

• Self-propelled flow
• Low Re flow Drag coefficient
• Computational fluid dynamics
• Biomedical fluid dynamics

Kendinden Tahrikli Mikro Organizmaların Newtonyen Akışkan İçindeki Harketinin Sayısal Modellenmesi

Öz

Mikro organizmaların hareketi gerek biyolojik davranışlarını anlamada gerekse mikro robot dizaynında önem taşımaktadır. Mikro yüzücü çoğu zaman durağan akışkanda oldukça düşük hızlarda kıvranma hareketi ile yer değiştirmektedir, bu da düşük Reynolds sayısından dolayı viskozitenin domine ettiği bir akıştır. Kıvranma hareketi yüzücünün sürüklenme kuvvetlerinin etkisini farklılaştırmaktadır. İleri, geri ve nötral moddaki hareketler için zamana bağlı periyodik kıvranma hareketi ANSYS® yazılımı ile modellenmiştir. Sonuçlar durağan duruma erişildikten sonraki tam bir periyod için akış çizgileri, hız vektörü eş eğrileri ve yüzücü çeperindeki duvar kesme kuvveti, girdaplılık ve sürükleme katsayısı değişimi olarak sunulmuştur. Kıvranan yüzücünün yüzme verimliliğinin hem Reynolds sayısına hem de yüzücü moduna bağlı olduğu gösterilmiştir.

Anahtar Kelimeler

• Kendinden tahrikli akış
• Düşük reynolds sayılı akış
• Sürükleme katsatısı
• Hesaplamalı akışkanlar mekaniği
• Biyomedikal akışkanlar mekaniği

Kaynakça

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