Performance analyses in parabolic trough collectors by inserting novel inclined curved-twisted baffles

The operation stability demands for low and uniform wall temperature in the parabolic trough collector which acts as an energy conversion component in concentrating thermal conversion technology. In order to reduce the local high temperature with moderate pump power consumption, this paper proposed longitudinal swirls impinging cooling method. Three types of novel inclined curved-twisted baffles (A1, A2, and A3) were devised to realize this method. With selecting the absorber tube as research model, this paper numerically compared the impinging cooling characteristics, wall temperature uniformity performance, and efficiency performance by inserting the three types of baffles. The A1 and A2 types each generated a pair of longitudinal swirls while the A3 type generated two pairs of longitudinal swirls. The impinging cooling always appeared near the front edge of inclined baffles. The A1 type was the best in wall temperature uniformity and efficiencies among three baffles. Furthermore, as the inlet temperature increased from 400 K to 600 K at a mass flow rate of 1.13 kg/s in the A1 type tube, the average wall temperature difference between bottom half tube and top half tube was decreased by 55.1%. Meanwhile, the average overall efficiency and exergy efficiency were increased by 0.52% and 0.22%, respectively. (C) 2020 Elsevier Ltd. All rights reserved.y

Automated summary

This study proposed a research on achieving the uniformity of wall temperature in the parabolic trough collector through the longitudinal swirls impinging cooling method. The comparison of three different baffles revealed that the A1 type baffle demonstrated the best performance in terms of wall temperature uniformity and efficiency.