Investigating solar air collector performance with different absorber surfaces and Piranha fins through numerical simulation

Researchers are constantly looking for ways to improve flat solar air heaters, which are a popular way to heat air using solar energy. This study looked at two different designs for the heat-absorbing surface (sinusoidal and plain) and how adding "Piranha fins" affected their performance. This research consisted of two parts. First, solar heaters with different absorber surfaces, including sinusoidal and plain, are investigated in two cases equipped with piranha fins and without fins. The second part will investigate the number of piranha fins (N). The results of the first part showed At a Reynolds number of 10,000, the sinusoidal absorber with Piranha fins achieved 23% efficiency, the sinusoidal absorber without fins reached 30%, and the plain absorber with fins only achieved 0.95% efficiency. The second part of the study demonstrated that increasing the fin count up to seven resulted in significant performance gains, with improvements of 30%, 28.5%, 23%, and 17% compared to the no-fin case for N = 7, N = 5, N = 3, respectively, at Re = 1000.