Eexperimental And Simulation Study On Thermal Performance Of The Air Solar Collector

The solar radiation energy is clean, renewable and abundant, so using it to realize heating is one effective way to ease the energy shortage problem and reduce the environment pollution, also it is the only way to achieve the sustainable development. As the core component of the whole solar heating system, improving the thermal performance of the solar collector has the important significance to promote the development of the solar heating technology. In addition to its own structure, the factors of collector’s thermal performance also include the air operationg flow, the solar radiation, ambient air temperarure and other operating parameters.To explore the thermal performance of air operating flow, a solar air collector system experimental platform was set up and the experimental study was carried out. Also the the numerical simulation model of collector plate’s performance was built by the CFD software and the simulation was done to analyse the factors influence on thermal performance parameters, the optimal operating flow were obtained according the simulation results of the thermal performance parameters under the corresponding conditions. The main research work are as follows:A solar air collector system experimental platform was built in this article, which consists of a solar radiation simulation device, solar collector and the test system. The experiment was done to get the thermal performances of the collector under the three air flow of0.94m3/h,1.41m3/h and1.87m3/h. The results demonstrated that the temperature of the solar collector plate were respectively39.74℃,36.99℃and35.19℃, the rise of air temperature were respectively22.45℃,17.57℃and14.37℃, and the thermal efficiency were respectively38.56%,45.13%and49.06%in the steady state of the three kinds of air flow.The numerical simulation model of collector plate’s performance was set up by the CFD software. By using the obtained experimental results, the author validated the numerical simulation model, and the simulation was carried out to get the thermal performance parameters under different conditions which the solar radiation was from300W/m2to700W/m2and the ambient temperature was from6℃to12℃were obtained by using the numerical simulation model According to the simulation results of performance parametres, such as the pressure loss of flow air, the temperature of collector plate’s surface, the outlet air temperature and the rise of air temperature, the thermal efficiency and the heat exchange effectiveness, the optimal operating flow of collector plate’s per unit area under corresponding conditions were obtained, which provided a reference for the selection of opertaing flow in the practical engineering, the design and economical operation of the solar air collector.