Applications of Modelling and Simulation (Jun 2020)
Performance Analysis of a Natural Phase Change Material-Based Solar Collector with Compound Parabolic Concentrator at Different Flow Rates
Abstract
The impact of a natural phase change material (PCM) based thermal solar collector, with a compound parabolic concentrator (CPC), was investigated during summer. This paper introduces a natural PCM (beeswax) instead of commercial phase change material, which was used as an energy storage media to improve the performance parameter of the solar collector. In this study, the natural phase change material was used within the solar collector, as it was easily available in nature. The outdoor experiments were carried out where compound parabolic concentrator, made of glass, was mounted on thermal collector during the day time. The data of consecutive three months have been collected and analyzed in this paper. The system performance, such as, thermal efficiency, operating value and collected energy of the collector were tested at a set different flow rate. The date was measured and compared between the systems with and without phase change material. Based on the measured collected energy and thermal efficiency, all parameter for the collectors as functions of water flow rate was obtained. This result shows that the maximum outlet water temperature of 50⁰C and the maximum thermal efficiency of 35-40% were achieved at a water flow rate of 0.004 kg/s. The system with PCM was illustrated to have much better performances. Phase change material was more effective to improve thermal efficiency in low solar radiation. The system reaches maximum plate temperature more quickly in June than in July and August. The highest absorber plate temperature reading found in June was 90⁰C and it took the system 3.5 hours to reach the point. ΔT/H operating value was inversely proportional to thermal efficiency. Water flow rate was proportional to collected energy and maximum collected energy was 456 W. It can be highlighted that the best water flow rate was 0.004 kg/s because it gives the maximum thermal efficiency and collected energy.
