SET Proceedings 2978-4387 Caravel Press 10.65582/set.2010.086 2010.086 Analysis and Simulation Study of Flow and Thermal Performance in the U-tube Solar Collector AnYujiao GaoYan LiDeying Dept. of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, China 24082010 9 978-1-995850-04-7 1 10 24 August 2010 © 2010 Copyright WSSET 2010

More investigations focused on the all-glassed evacuated tube solar collector, less concentrated on the U-tube solar collector. In this study, according to the heat transfer theory, the energy balance equations for U-tube solar collector were established. In order to analyze the collector thermal efficiency in detail, a computational fluid dynamics model was developed for different operating conditions. By varying the inlet flow velocity, different solar irradiance and varied configuration. Simulation results presented that faster incoming flow rate, lower solar irradiance or bigger U-tube diameter will lead to lower outlet temperature, whereas faster incoming flow rate, higher solar irradiance or bigger U-tube diameter result in higher thermal efficiency. Furthermore, within the specified range ，the flow structure in the U-tube uninfluenced by the inlet flow rate. In addition, comparison of all the acting factors related to the thermal efficiency, the U-tube diameter relatively made largest impact on improving the solar collector thermal characteristics.

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