The Interval Analysis for Uncertainty Heat Transfer Process of Phase Change Thermal Storage Based on Perturbation Method

Due to phase change materials (PCMs) composition, machining error, measuring error and other factors, the PCMs thermal physical properties, geometric properties, etc are usually uncertain. As a result, phase change heat transfer process is an uncertainty heat transfer process. But at present, heat transfer characteristics research on phase change thermal storage are all based on certainty heat transfer models (Taken uncertainty factors as certainty factors). In this paper, it is considered factors uncertainty influencing phase change thermal storage heat transfer process. By looked on the variation scope of influence factors as "interval number", based on interval mathematics, perturbation method and finite difference method, "interval number" heat transfer model of phase change thermal storage is established. In this model, the uncertainty variables are decomposed into the sum of the nominal value and the deviation value. PCM uncertainty temperature field can be determined by calculated nominal value and the deviation value of PCM temperature field separately. Comparison between simulation results of the model and experimental data implies that it is necessary to consider influencing factors uncertainty in phase change thermal storage heat transfer analysis.