A numerical study of solar air collectors with corrugated absorber plates featuring diverse wave amplitudes and wavelengths

Abstract

The impact of varied surface textures, characterized by differing amplitudes and wavelengths, on heat transfer rates and friction factors of absorber plates in solar air collectors has been investigated via numerical simulations. Novel geometric configurations of corrugated absorber plates were explored, with a thorough assessment of collector performance. Analyses encompassed the influence of key parameters including Reynolds number, wave amplitude, wavelength, relative amplitude, and relative wavelength. Investigations had been conducted across a Reynolds number range from 3.8 × 10³ to 18 × 10³. Utilizing the ANSYS FLUENT code, a 2-D computational fluid dynamics simulation was executed, choosing the renormalization group (RNG) model from the k-ɛ model as the best fit. The results from smooth duct scenarios were compared with the effects of all the characteristics that were taken into consideration on the friction factor and heat transfer. Optimal heat transfer rates were observed at a relative amplitude of 0.03 and a relative wavelength of 15, while maximum flow friction factors were noted at a relative amplitude of 0.09 and a relative wavelength of 5. Furthermore, the highest values for thermal enhancement factor, relative amplitude, and relative wavelengths, reaching 1.84, 0.03, and 15, respectively, were identified for a Reynolds number of 12,000.