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Experimental study of transient cooling of fluid inside closed reservoir by using CuO/water nanofluid

Mohsen Nazari

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Nasibe Babazade-baie, Mohammad Mohsen Shahmardan, Mojtaba Ashouri

Department of Mechanical Engineering, University of Shahrood, Shahrood, Iran

*P.O.B. 3619995161, Shahrood, Iran mnazari@shahroodut.ac.ir

A RTICLE I NFORMATION A BSTRACT

Original Research Paper Received 30 January 2015 Accepted 12 February 2015 Available Online 07 March 2015

Transient heat transfer from storage fluid around central tube is experimentally investigated at wide range of Reynolds number, i.e. 700<Re<5500. The CuO/Water nano luid in two volume fractions of 0.1 and 0.2 is employed as the coolant luid inside the central tube. The pure water at the initial temperature of 70^O is used inside the storage tank which is cooled by the nanofluid flow. The temperature of the coolant at the inlet of the central tube is kept constant during the test. By measuring the inlet and outlet fluid temperature of the central tube and also the mean temperature of the storage tank, the averaged Nusselt number and the related Rayleigh numbers have been reported. Also, the pressure drop of nanofluids has been measured. The accuracy of the experimental results has also been validated by the presented experimental and theoretical data which show good agreement between the results. The obtained results have been reported by using the confidence interval error bars. The result shows considerable increase in the Nusslet number (about 20 %) and decrease in the dimensionless storage tank temperature (about 1 %) by using nanofluids instead of pure water. Both heat transfer and pressure drop of nanofluid in different volume fractions have been reported and discussed.

Keywords:

Convective Heat Transfer Transient flow Nanofluids

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