Jet impingement cooling using shear thinning nanofluid under the combined effects of inclined separated partition at the inlet and magnetic field

Abstract

Combined effects of using inclined partition and magnetic field on the cooling performance of double slot jet impingement are analyzed with finite element method. Two different shear thinning nanofluids are used while experimental data is available for the rheological properties. Different values of of Reynolds number (Re between 100 and 1000), velocity ratio (VR, between 0.2 and 1), opening ratio (OR, between 0.05 and 0.95), magnetic field strength (Ha, between 0 and 30) and inclination of partition (f2, between 0 and 40) are used. It is observed that varying VR of the jets, size/inclination of the partition, magnetic field strength and nanfluid type, can be used to control the local and average convective heat transfer and cooling performance features effectively. The average Nusselt number (Nu) rises with higher VR while at the highest VR the amount of increments are 23.5% and 28.5% with first (NFl) and second (NF2) nanofluid (NF). When magnetic field is imposed, effects of OR becomes important with NF1 at the lowest strength of magnetic field. Average Nu reduces with higher magnetic field strength for NF1 while 14.4% reduction for the highest strength at OR = 0.95 is achieved. However, for NF2 the trend is opposite and 18.8% increment is obtained. Variations in the average Nu becomes 7.6% and 1.8% for NFl and NF2 when inclination of the partition is changed. The cooling performance is estimated by using a feed-forward network modeling approach in terms of average Nu for NFl and NF2 by using 25 neuron in the hidden layer.