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This paper presents an experimental investigation on the thermal performance enhancement of solar air heater having wavy fins attached below the absorber plate. Tests were conducted to cover a wide range of parameters such as mass, velocity, fin spacing and insolation under actual outdoor conditions. The effect of these parameters on the thermal performance has been examined and the results have been compared with plane solar air heater. The maximum enhancement in thermal efficiency for wavy finned absorber solar air heater for fin spacing of 2 cm has been found to be 28.71% as compared to fin spacing of 6 cm and 116.67% as compared to plane solar air heater. The maximum value of ∆T/I for wavy fin spacing 2 cm, 6 cm and plane solar air heater has been achieved as 0.067, 0.048 and 0.029 m2-°C/W respectively. Wavy finned absorber solar air heater has been found to be 67.44 to 121.43% thermally efficient as compared to plane solar air heater within the investigated range of system i.e. fin spacing of 2 to 6 cm and operating parameters i.e. mass velocity of 0.0065 - 0.033 kg/s-m2. A substantial enhancement in thermal efficiency was achieved in comparison to plane solar air heater and this improvement is a strong function of system and operating parameters.
wavy fin., thermal performance, fin spacing, mass velocity
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