Accelerated testing methods to analyse long term stability of a Phase Change Material under the combined effect of shear stress and thermal cycling

• DOI: 10.1016/j.est.2022.105867
• Publication Date: 2022-10-25T22:31:22Z
• Authors: A. Egea; A. García; R. Herrero-Martín; J. Pérez-García
• Keywords: Temperature cycling; Paraffin wax; Phase-change material

The long-term stability of a Phase Change Material (PCM) is key point for its selection in energy storage devices. This work studies the suitability commercial paraffin wax an active scraped surface heat exchanger solar purposes. In these devices, continuous scraping inner walls during solidification removes PCM and increases released heat. Hence, affected by high level shear stress. order to study potential degradation paraffin, novel accelerated procedure has been designed obtaining samples with different number thermal cycles. allows evaluate effect stresses, cycles their combined effects separately. Up 3000 have generated, which accounts around 8 years daily exchanger. measurements through Differential Scanning Calorimetry, rheometry conductivity analysis shown that neither nor cycling significant impact on thermo-physical properties. According findings reported this work, RT44HC can be successfully used exchangers. It expected other paraffins would also suitable since most them share fact being blends alkanes hydrocarbons.