$Al_2O_3$-Su Nanoakışkanının Manyetik Alan Altında Akış Karakteristiklerinin Sayısal Analizi

Bu çalışmada, manyetik alan altındaki bir boruda Al2O3–su nanoakışkanının akış karakteristikleri laminer şartlar altında sayısal olarak incelenmiştir. Çalışma ANSYS-FLUENT ticari yazılım programı ile gerçekleştirilmiştir. Manyetik alan akış yönüne dik verilmiştir. Akışkan sıcaklığı (Ti) boru sıcaklığından (Tw) daha yüksek tutularak akışkanın soğuması sağlanmıştır (Ti > Tw). Reynolds sayısı (Re) = 10, 100, 500, 1000, 2000, Hartmann sayısı (Ha) = 0, 25, 50, 100 ve nanopartikül hacimsel oranı (φ) = 0, 0.01, 0.03, 0.05 olarak seçilmiştir. Akışkan hız değişimleri ve basınç değişimleri detaylı olarak incelenmiştir. Akışkan hızı, manyetik alan ve nanopartikül hacimsel oranı ile azalırken, boru merkez uzunluğu boyunca basınç değerleri artmıştır. Manyetik alan ile meydana gelen hız düşüşü nanopartikül eklenmesi ile meydana gelen düşüşten daha fazladır. Aynı şekilde, manyetik alan ile meydana gelen basınç artışı, nanopartikül eklenmesi ile meydana gelen basınç artışından daha fazladır. Sonuç olarak, hem manyetik alan kuvveti hem de nanopartikül ilavesi akışkan hareketi üzerinde etkilidir. Ayrıca, manyetik alan kuvveti ile nanoakışkan hareketi kontrol altında tutulabilir.

Numerical Analysis of Flow Characteristics of $Al_2O_3$-Water Nanofluid Under Magnetic Field

In this study, the flow characteristics of Al2O3-water nanofluid in a pipe under magnetic field have investigated numerically under laminar conditions. The study has carried out with the ANSYS-FLUENT commercial software program. Magnetic field is given perpendicularly to the flow. Fluid temperature (Ti) was kept higher than the pipe temperature (Tw), allowing the fluid to cool (Ti > Tw). Reynolds numbers (Re)=10, 100, 500, 1000, 2000, Hartmann numbers (Ha)=0, 25, 50, 100, and nanoparticle volume fractions (φ)=0, 0.01, 0.03, 0.05 have chosen. Fluid velocity and pressure changes are examined in detail. Fluid velocity has decreased with magnetic field and nanofluid volume ratio, while fluid pressure has increased along the center length of the pipe. The velocity drop caused by the magnetic field is greater than that caused by the addition of nanoparticles. Likewise, the pressure increase caused by the magnetic field is higher than the pressure increase caused by the addition of nanoparticles. As a result, both magnetic field strength and nanoparticle addition have an effect on fluid motion. Also, the motion of the nanofluid can be kept under control with the magnetic field.

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