Performance of solar collector with turbulator involving nanomaterial turbulent regime

In current attempt, swirl generator and four-lobed pipe were installed in a solar collector to achieve higher performance not only in view of cooling rate but also available energy. In outputs, components of irreversibility were illustrated for different values of revolution (N), pumping power (Re (Reynolds number)) and width of tapes (D*(diameter ratio)). Four functions were scrutinized namely; Xd (exergy loss); S-gen,S-th (thermal irreversibility); S-gen,S-f (frictional irreversibility); Phi(s) (Augmented irreversibility). Experimental articles were utilized to not only verify the nanofluid modeling but also the correctness of selecting k-epsilon turbulent model. S-gen,S-th declines with rise of active parameters because of reduction in temperature gradient and highest impact belongs to Re. Although increasing revolution provides stronger secondary flow as well as trend of Re, the influence of N on S-gen,S-th is lower than that of Re. At lowest values of other factors, Be (Bejan number) declines about 0.016%, 0.004% and 8.2% with enhance of diameter ratio, N and Re. Revolution of tape has lowest impact on Be in comparison to other factors. Be decreases about 1.67% with rise of N at Re = 20000, D* = 0.045. The component of del T reduces as greater secondary vortex appears. So, augment of inlet velocity, width and revolution of tape makes exergy loss to decline. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The installation of a swirl generator and a four-lobed pipe in a solar collector aims to improve performance and reduce exergy loss. Experimental results show that certain active parameters lead to a decrease in thermal irreversibility, while the Bejan number decreases with an increase in diameter ratio, revolution speed, and Reynolds number.