Thermal performance analysis of solar air collectors with different flow models

Purpose of this study is to determine the performances of the solar air collectors newly designed and implemented with different flow models. Three different collectors having different flow models were designed and manufactured for this study. First collector was produced so as to have single pass only through the channel under the absorber plate. Second collector was designed with single pass double flow through the channels both under and over the absorber plate. Third collector was with single flow double pass in which firstly flow passes over the absorber plate and then externally returns and passes through under the absorber plate. Performances of the flat plate solar air collectors which are designed and implemented considering different flow types have been measured experimentally under the climatic conditions of Konya/Turkey. Experiments were performed with different air mass flow rates as working fluid in the collectors. Daily changes in the temperatures and thermal performances of the all collector types were determined. Besides effects of the mass flow rate and solar radiation intensity on the collector performance were investigated. Keywords: Solar air collector, double pass, external recycle, thermal efficiency.