3.2. Heat collecting efficiency
3.2.1. The effect of mass fraction
In order to study the performance of nanofluids as the working
fluids in the solar collector system, each experimentwas performed
four times and the good datas were chosed to analyze. Fig 7 shows
an example of typical recorded data for water and nanofluids
(Cu:25 nm, 0.1 wt%) at 140 L/h in one of the test days. The inlet fluid
temperature is almost remain unchanged, the outlet fluid temperature
is the critical parameter. As can be seen from Fig. 7, before