Effect of thermal parameters on heat storage and release performance of phase change material composite wall

Abstract

In order to enlarge and improve the application of phase changing materials (PCM) composite wall in Chinese solar greenhouse (CSG), the effect of thermal parameters on heat storage and release performance of PCM composite wall were systematically and scientifically investigated by available CFD code of commercial software ANSYS-Fluent, which was almost determined by the parameters such as density, thermal conductive, latent heat fusion and specific heat capacity. The numerical simulation was reasonably validated by the experimental result under the same condition, which was conducted by error analysis of interval analysis (IA) method. The result is shown that IA result between numerical simulation and experiment is 0.96, while the numerical simulation of PCM composite wall is significantly accurate and reliable. The maximum temperature of the center point in interior surface is completely dependent on the contrary tendency changing of thermal parameters at heating time, of which is directly proportional to thermal parameters changing at cooling time, except the specific heat capacity. While only the thermal conductivity increasing is benefit for increasing interior surface temperature of PCM composite wall at final cooling time. The effect of solely thermal parameter on the heat storage and release performance changing of PCM composite wall is from strength to weaken: density changing ( Δ ρ ) > thermal conductivity changing ( Δ K m ) > latent heat fusion of liquid changing ( Δ H ) > specific heat capacity changing ( Δ C p ).