Heat transfer enhancement in a PV cell using Boehmite nanofluid

Experiments were conducted to investigate the cooling performance of channels by water-based nanofluids containing small concentrations of Boehmite (AlOOH center dot xH(2)O) for the PV cell. The channels were fabricated in two different configurations as straight and helical. The straight channel consists of 23 parallel rectangular channels with a hydraulic diameter of 4.1 mm, a length of 24.5 cm, a width of 5 mm and a depth of 3.5 mm. For the helical configuration the plate was divided into four symmetrical sections which, each part contains a helical channel with a width of 5 mm, a depth of 3.5 mm and a hydraulic diameter of 4.1 mm. The nanofluid cooling performance was assessed from the results obtained for the average temperature and electrical output of the PV cell. Results showed that the nanofluid perform better than water and caused higher decrease in the average PV cell temperature. They were about 39.70% and 53.76% for 0.1 wt.% (the best case) at flow rate of 80 ml/min for the helical and straight channel, respectively. Moreover, the highest decrease of average temperature relative to the reference temperature was observed for 0.1 wt.% nanofluid concentration in both channels. This led to the highest electrical efficiency about 20.57% and 37.67% for the straight and helical channel, respectively. Furthermore, power-hydraulics performance was defined to compare the performance of the studied channels. The results showed that the helical channel works in more efficient way compared with the straight one. (C) 2014 Elsevier Ltd. All rights reserved.