The Effect of Using Transverse Partitioning and Reflection on Single and Counter Flow Solar Air Heater Using Wire Mesh as an Absorber

ABSTRACT: Rising costs of conventional fuels, increasing energy demand, concerns over climate change and pollutants resulted from burning fossil fuels have increased the interest in various renewable energy technologies. The energy demand associated with heated air for different sectors is quite significant. Solar air heaters have been developed with the aim of reducing the demand for conventional fuels. 3 glazed solar air heaters were experimentally studied here. The thermal performance of a single and counter path solar air heater with 2, 4, and 6 fins attached were experimentally investigated. The effect of reflection on the single path solar air heater with 2 fins was studied. Wire mesh layers were used between the fins instead of an absorber plate. The effects of mass flow rate of air on the outlet temperature and thermal efficiency were studied. The indicated results show that the efficiency always increases with increasing the mass flow rate for the range of the flow rate used in this work. The maximum efficiencies obtained for the counter pass solar air heater (CPSAH), and the single pass solar air heater (SPSAH) for the 6 fins case and mass flow rate of 0.042 kg/s were 85.9% and, 79.8% respectively. While the maximum efficiency obtained for single pass solar air heater with reflection (SPSAHWR) was 56.1% compared to 65.8% for the 2 fins SPSAH case and same mass flow rate. In addition, the maximum instantaneous temperature difference obtained for CPSAH, and SPSAH, was 62.1 oC, 51 oC, respectively for the 6 fins SAH when the mass flow rate was 0.0121 kg/s. While the maximum instantaneous temperature difference obtained for SPSAHWR was 51.1 oC compared to 44.2 oC of SPSAH of the same mass flow rate. Comparison of the results of CPSAH, SPSAH and SPSAHWR collectors with those of a conventional collector shows a substantial enhancement in the thermal efficiency. Keywords: Renewable energy, solar air heaters, counter path solar air heater with fins, single path solar air heater with fins, thermal efficiency. ……………………………………………………………………………………………………………………………………………………………………………………………………………………