Performance study of a novel solar air collector

A novel solar air collector of pin-fin integrated absorber was designed to increase the thermal efficiency. According to experimental results, the average thermal efficiency of twenty-five kinds of pin-fin arrays collector reach 0.5–0.74 compared to the solar transmittance of 0.83 for the glazing. A correlation equation can be put forward to reflect the maximum thermal efficiency (ηmax) of twenty-five kinds of pin-fin arrays collectors as function of dimensionless pin-fin span (s/d) and dimensionless pin-fin height (h/d). By theoretical calculation, the mathematic models of thermal efficiency of twenty-six collectors including flat-plate collector are obtained representing the influences of solar irradiation and inlet conditions of air stream on thermal efficiency. In the performance analysis of varying flow rate on PZ7-11.25 pin-fin arrays collector, the correlation equation on heat transfer coefficient is obtained and the efficiency variation vs. air flow rate is determined in this work.