Spiral Isı Eşanjöründe Farklı Su-Al2O3Nanoakışkan Karışımlarının Termal Davranışlarının Karşılaştırılması

Abstract

Son zamanlarda nanoteknolojinin gelişmesi, baz akışkanların ısı transfer özelliklerini geliştirmek için kullanılması fikrinin kullanılmasında artış olmuştur. Özellikle ısı eşanjörlerinde nanoakışkanların kullanılması yaygınlaşmıştır. Bu çalışmada, spiral bir ısı eşanjöründe farklı Al2O3 su nanoakışkan karışımlarının termal davranışlarının karşılaştırılması nümerik olarak incelenmiştir. Spiral ısı eşanjöründeki ısı transferinin bilgisayar destekli analizi su ve su bazlı nanoakışkanlar üzerinde yapılmıştır. Nanoakışkanlar içerisindeki Al2O3 nanoparçacığının farklı hacim konsantrasyonları (%1, %2 ve %3) ve su özellikleri belirlenerek, spiral bir ısı eşanjöründe analizleri gerçekleştirilmiştir. Nanoakışkanların termo fiziksel özelliklerinin nanopartiküllerin hacim konsantrasyonlarına ve sıcaklığa bağlı olarak değişimi gözlemlenmiştir. Isı transferi ve ortalama ısı transfer katsayısı, nanopartiküllerin farklı hacim konsantrasyonları için sayısal olarak hesaplanmış ve elde edilen sonuçlar karşılaştırılmıştır. Çalışmadaki farklı hacim konsantrasyonları arasında en iyi sonuçlar %3 hacim konsantrasyonuna sahip nanoakışkanda elde dilmiştir. Ayrıca %3 hacim konsantrasyonuna sahip nanoakışkanda suya göre ısı transferinin %47 ve toplam ısı transfer katsayısının %24 daha iyi olduğu hesaplanmıştır.

Keywords

• Spiral Isı Eşanjörü
• Nanoakışkan
• Su/AL2O3
• CFD

Comparison of Thermal Behaviors of Different Water/Al2O3 Nanofluid Mixtures in a Spiral Heat Exchanger

Abstract

Recently, with the development of nanotechnology, there has been an increase in the use of the idea of using base fluids to improve heat transfer properties. The use of nanofluids, especially in heat exchangers, has become widespread. In this study, the comparison of the thermal behavior of different Al2O3 water nanofluid mixtures in a spiral heat exchanger was investigated numerically. Computer aided analysis of the heat transfer in the spiral heat exchanger was carried out on water and water-based nanofluids. Different volume concentrations (1%, 2% and 3%) and water properties of Al2O3 nanoparticles in nanofluids were determined and analyzed in a spiral heat exchanger. It was observed that the thermophysical properties of nanofluids change depending on the volume concentration of the nanoparticles and the temperature. Heat transfer and average heat transfer coefficient were calculated numerically for different volume concentrations of nanoparticles, and the obtained results were compared. Among the different volume concentrations in the study, the best results were obtained in the nanofluid with 3% volume concentration. In addition, it has been calculated that the heat transfer is 47% better, and the total heat transfer coefficient is 24% better than water in the nanofluid with 3% volume concentration.

Keywords

• Spiral Heat Exchangers
• Nanofluids
• Water/AL2O3
• CFD

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