EFFICIENCY OF LIQUID FLAT-PLATE SOLAR ENERGY COLLECTOR WITH SOLAR TRACKING SYSTEM

An extensive testing programme is performed on a solar collector experimental set-up, installed on a location in town of Shtip (Republic of Macedonia), latitude 41 degrees 45' and longitude 22 degrees 12', in order to investigate the effect of the Sun tracking system implementation on the collector efficiency. The set-up consists of two flat-plate solar collectors, one with a fixed surface tilted at 30 towards the south, and the other one equipped with dual-axis rotation system. The study includes development of a 3-D mathematical model of the collectors system and a numerical simulation programme, based on the computational fluid dynamics approach. The main aim of the mathematical modelling is to provide information on conduction, convection, and radiation heat transfer, so as to simulate the heat transfer performances and the energy capture capabilities of the fixed and moving collectors in various operating modes. The feasibility of the proposed method was confirmed by experimental verification, showing significant increase of the daily energy capture by the moving collector, compared to the immobile collector unit. The comparative analysis demonstrates a good agreement between the experimental and numerically predicted results at different running conditions, which is a proof that the presented computational fluid dynamics modelling approach can be used for further investigations of different solar collectors configurations and flow schemes.