Electromechanical Eng. Dep., University of Technology, Baghdad, Iraq.
Novel techniques to enhance thermal performance using a helical coil receiver tube and Nano-fluid materials are presented in this paper. Two different applied techniques to enhance thermal performance are used as a new application on parabolic trough solar collector (PTSC). In the present work, PTSC has been fabricated using Dioxide Silicon SiO2 with an average particle size of 40nm by taking volume fraction of SiO2 0.1, 0.2 and 0.3%. Distilled water based Nano-fluid as a working fluid and a helical coil receiver tube were used in this paper. Varying the flow rate of Nano-fluids 100,150 and 200l/h are used, respectively. A solar tracking mechanism experimentally has been used with the PTSC. As per ASHRAE standard, the experimental results showed that at volume fraction 0.3 % and flow rate of 200 l/h, the highest increase in the energy absorbed factor FR(τα) was 14.6 % and energy removal factor FRUL was 29.4 % compared with distilled water. The changes in FR(τα) vary from 11.8% to 14.6% while in FRUL, they vary from 20.5% to 29.4% as compared with the distilled water case. The maximum efficiency was about 76.6 % as the heat loss parameter [(Ti–Ta)/GT] =0 at a volume fraction of 0.3 % and the flow rate of 200 l/h.
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