الفهرس | Only 14 pages are availabe for public view |
Abstract In this thesis, a double pass solar air heater with a corrugated absorber plate and built-in external reflector is adopted to improve its thermo-hydraulic performance. The proposed solar air heater is tested with five tilt angles: 0°, 5°, 10°, 15° and 20°. Data obtained from the proposed heater are compared with the conventional design without reflector under a typical six air flow rate 11, 13, 15, 17, 20 and 25 l/s. The measured results are reported based on some parameters such as thermal, exergy, thermo-hydraulic efficiencies, cost heat unit and temperature differences. The heater with external reflector improves the performance parameters when compared with the conventional heater. Also, increasing the air flow rate enhances thermal and thermo-hydraulic efficiencies and reduces the production cost. The energy input configuration has been shown to be the superior effect on the enhancement of heater performance than the others effects. The maximum effectiveness and achieved average temperature differences for proposed heater were 0.74 and 26.5 °C, respectively. The maximum improvements in average thermal and thermo-hydraulic efficiencies for proposed heater were 19.33 % and 19.84 % respectively. The maximum value and enhancement ratio of average exergy efficiency for proposed heater was 1.14 % and 27.01 % respectively. The optimum cost heat unit is achieved using proposed heater estimated by about 0.0047 $ and maximum 93.11 % reduction. The optimum values of the performance parameters of the proposed heater under study are obtained when the mass flow rate of flowing air and tilt angle are 25 l/s and 20° respectively. |