Nanofluid thermal performance inside an absorber tube of LFR unit equipped with helical T-shape tape

Abstract

Entropy generation and thermal treatment of nanofluid through a solar unit with turbulent regime was examined in current investigation. To create the solar system, mirrors, trapezoidal cavity and tube have been utilized. The mirrors were situated above the ground with certain angles and tube was equipped with turbulator. Working fluid is homogeneous mixture of H2O-Al2O3 and temperature dependent variables were incorporated. Verification based on empirical correlation depicts the high accuracy of FVM simulation. Irreversibility components and friction resistance as well as Nu and thermal efficiency have been reported in outputs. The active variables are Twist ratio (TR), V·, Width ratio (WR), Tin. Each factor which can augment the secondary flow makes the stronger impingement of fluid with wall and lower Tw appears. Such disruption of boundary layer causes cooling rate to augment. As V·, TR and WR augment, wall temperature reduces about 1.01%, 0.063% and 0.0217%. With rise of TR and WR, pressure drop augments about 25.87% and 10.85%, respectively. Revolution number has greater impact on resistance of fluid than width of the tape. Augment of WR and TR makes friction resistance to augment about 7.46% and 29.68%. Considering greater WR and TR can able to more disturb the boundary layer and Nu can be augmented about 1.5% and 4.54%, respectively. Augmenting TR, WR and Re can reduce the irreversibility which is a pleasant result to obtain more available work. Augment of TR makes Sgen,h to decline by 3.29% while Sgen,f rises about 15.24%. Thermal performance decreases about 23.68% with rise of Tin while it augments about 0.027% and 0.11% with growth of WR and TR, respectively.