Fundamental Study of the Thermal Performance of a Solar Collector with Evacuated Tube for Solar Heating System

摘要

In this paper, the thermal performance of a solar collector with evacuated tube is investigated. Main application for this collector is water heating for domestic or large building, several parameters may affect the performance of the collector, such as the water flow-rate, the different irradiance, the variable inlet water temperature, the flow configuration (series or parallel connection of tubes) etc. These parameters may all be considered in the effort to optimize the overall design. In this study efficiency curves are presented from experimental measurements. And the fit equation of efficiency is provided. After a long period test, the actual efficiency curve in different months will be compared together. Also, the test results in a certain day are presented in order to analyze the comprehensive relationship among inlet temperature, ambient temperature and solar irradiance. Besides, the results of this procedure test can be very useful, firstly, for the local solar manufacturers' equipment in order to design and optimize its products and secondly, by the engineers in order to select and design the most suitable system.