کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
668723 1458738 2014 18 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Experimental investigation of CuO–water nanofluid flow and heat transfer inside a microchannel heat sink
موضوعات مرتبط
مهندسی و علوم پایه مهندسی شیمی جریان سیال و فرایندهای انتقال
پیش نمایش صفحه اول مقاله
Experimental investigation of CuO–water nanofluid flow and heat transfer inside a microchannel heat sink
چکیده انگلیسی


• Experimental study of 29 nm CuO–water nanofluid in a microchannel heat sink.
• Tests performed up to Re ≈ 5000 (isothermal) and to ≈2500 (heated cases).
• Slight heat transfer enhancement observed for low particle volume fractions.
• Important increase of friction factor and pressure drop compared to water.
• Early transition to turbulence at Rec ≈ 1000 for both water and nanofluids.

This paper presents an experimental investigation of the hydraulic and thermal fields of a 29 nm CuO nanoparticle–water nanofluid with various volume fractions, 0.24%, 1.03% and 4.5% flowing inside a rectangular microchannel heat sink under both laminar and turbulent conditions. The isothermal and heated tests are conducted for Reynolds number up to ≈5000 and to ≈2500, respectively. For a given fluid flow rate experimental results show an increase of the pressure drop and the friction factor with respect to water. This increase can be as high as 70%, 25%, and 0–30%, respectively, for the 4.5%, 1.03%, and 0.24% particle volume fractions. Although the laminar-to-turbulent transition was observed at nearly the same critical Reynolds number Rec ≈ 1000 for water and the tested nanofluids, this value of Rec is clearly lower than that corresponding to a smooth surface microchannel. Results show a slight heat transfer enhancement with respect to water for nanofluids with low particle volume fractions, 0.24% and 1.03%, while for the 4.5% fraction a clear decrease of heat transfer was found. In general, the nanofluid overall energetic performance, defined by the heat transferred/pumping power ratio, remains lower than that of water for a given Reynolds number. This ratio decreases with an augmentation of the particle volume fraction.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: International Journal of Thermal Sciences - Volume 84, October 2014, Pages 275–292
نویسندگان
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