Radiation and convection treatment of nanomaterial within a Linear Fresnel Reflector unit
Renewable Energy Systems and Nanofluid Applications in Heat Transfer Laboratory, Babol Noshirvani University of Technology, Babol, Iran
2 Department of Mechanical Engineering, Babol Noshirvani University of Technology, Babol, Iran
Accepted: 21 January 2021
Published online: 11 February 2021
To absorb more solar flux, the tube of LFR system was equipped with Y-shaped fins in current investigation. The fluid in tube is H2O with inclusion of alumina nanoparticles. Installing mirrors with special angles and installing parabolic reflector above the tube lead to greatest optical performance. Turbulent regime was assumed and K-ɛ approach was used for modeling. Reasonable accommodation with data of empirical correlations indicates nice accuracy of simulation. Influences of operation factors on carrier fluid thermal behavior were presented. Also, exergy efficiency, irreversibility and Be were scrutinized. DO model with employment of conditions of pure radiation was utilized to compute the solar heat flux. Better flow mixing takes places if values of Vin, L1 and L2 augment because residence time grows. Increase in Tin offers lower cooling rate and higher wall temperature appears. Increasing Vin, L1 and L2 makes tube temperature to decline about 0.457%, 0.109% and 0.194% with assuming lowest level of other factors. Also, increasing Tin offers augmentation of tube temperature about 9.93%. Darcy factor drops with grow of L1 and L2 about 47.27% and 37.42% when Vin = 0.16, Tin = 293.15 K. As Vin augments, Nu intensifies about 82.71% when L1 = L2 = 2 mm. Nu increases with augment of L1 about 15.67%. Sgen,h declines about 9.82% with augment of L1 while Sgen,f augments about 51.68% with rise of this variable. Be decreases about 1.13% and 0.108% with intensify of Vin and L2, respectively. The value of augments with rise of Vin about 1.08% while it reduces about 23.43% with growth of Tin. With rise of L1, and enhance about 0.67% and 0.09% when L2 = 2 mm, Vin = 0.16, Tin = 293.15 K.
© The Author(s), under exclusive licence to Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2021