Evacuated tube solar collectors integrated with phase change materials and silicone oil
Conference
Papadimitratos, A, Sobhansarbandi, S, Pozdin, V et al. (2017). Evacuated tube solar collectors integrated with phase change materials and silicone oil
. 2 10.1115/POWER-ICOPE2017-3520
Papadimitratos, A, Sobhansarbandi, S, Pozdin, V et al. (2017). Evacuated tube solar collectors integrated with phase change materials and silicone oil
. 2 10.1115/POWER-ICOPE2017-3520
This paper presents a novel method of integrating Phase Change Materials (PCMs) and Silicone oil within the Evacu- ated solar Tube Collectors (ETCs) for application in Solar Wa- ter Heaters (SWHs). In this method, heat pipe is immersed inside the phase change material, where heat is effectively accumulated and stored for an extended period of time due to thermal insula- tion of evacuated tubes. The proposed solar collector utilizes two distinct phase change materials (dual-PCM), namely Tritri- acontane paraffin and Erythritol, with melting temperature 72°C and 118°C respectively. The integration of Silicone oil for uni- form melting of the PCMs, utilizes the convective heat transfer inside the evacuated tubes, as this liquid polymerized material is well known for its temperature-stability and an excellent heat transfer medium. The operation of solar water heater with the proposed solar collector is investigated during both normal and stagnation (on-demand) operation. The feasibility of this tech- nology is tested via small scale and large scale commercial solar water heaters. Beyond the improved functionality for solar water heater systems, the results from this study show show efficiency improvement of 26% for the normal operation and 66% for the stagnation mode compared with standard solar water heaters that lack phase change materials and silicone oil. The benefit of this method includes improved functionality by delayed release of heat, thus providing hot water during the hours of high de- mand or when solar intensity is insufficient such in a cloudy day and during night time.
