Abstract
The present study experimentally investigated the thermal efficiency, collector area, weight, embodied energy, environmental CO
2
emissions of Al
2
O
3
/water nanofluid flow in a flat-plate solar collector and with coiled wire turbulators. The experiments were performed at
ϕ
that is equal to 0.1%, 0.2% and 0.3% and volume flow rate from 120 to 300 L/h. Results indicate that the collector thermal efficiency increased with the increase of particle volume loadings and volume flow rates. The thermal efficiency of the collector with water circulate is 53%, whereas it is enhanced to 65% at
ϕ
= 0.3% nanofluid, and it is further enhanced to 77% for
ϕ
= 0.3% nanofluid with 10-mm coiled wire insert in a collector tube at a volume flow rate of 300 L/h. The collector area is declined to 8.66% (
ϕ
= 0.1%), 14% (
ϕ
= 0.2%) and 18.66% (
ϕ
= 0.3%) for nanofluids. The collector area is further reduced to 31.33% for
ϕ
= 0.3% nanofluid and with a coiled wire pitch of 10 mm. The materials embodied energy is decreased to 1144.36 MJ for
ϕ
= 0.3% nanofluid, and it is further reduced to 1022.6 MJ with the use of a wire coil pitch of 10 mm, but for water, it is 1451.4 MJ. The Nusselt number is increased to 23.22% with
ϕ
= 0.3% nanofluid, and it further enhanced to 53.56% at same particle loadings and coiled wire pitch of 10 mm over the water data.