Experimental studies on booster lens thermosyphon solar water heating system

Experimental studies on real conventional and modified thermosyphon (booster lens) solar flat plate collectors have been carried out from 9.00 am to 4.00 pm in open atmosphere. The mass flow rate, instantaneous heat gain and efficiency increase gradually from 9.30 am to 1.30 pm and decreases from 1.30 pm to 4.00 pm. The average mass flow rate obtained by booster lens collector is compared to conventional and is 18.1%. The highest heat gain noticed at 1.30 pm is 375.51 J s −1 and 439.97 J s −1 for real conventional and modified thermosyphon collector, respectively. Experimental outcome exposed that the average heat intensification and thermal performance for modified thermosyphon collector have 24.25% and 25.1% higher than the real conventional one. The experimental nusselt number and friction factor compared with Sieder-Tate and fanning equation and deviation falls with in 7.41% and 14% respectively.