Study on the influence of thermo-physical parameters of phase change material panel on the indoor thermal environment of passive solar buildings in Tibet. (25th August 2022)

• Record Type: Journal Article
• Authors: Zhang, Yangkai; Sang, Guochen; Li, Pan; Du, Mengjie; Guo, Teng; Cui, Xiaoling; Zhang, Lei; Han, Weixiao
• Is Part Of: Journal of energy storage. Volume 52:Part C(2022)
• Publication Date: 2022-08-25
• Subjects: c Specific heat, J·kg−1·K -1 -- ce Equivalent specific heat of PCM panel, J·kg−1·K -1 -- cl Specific heat of PCM in solid state, J·kg−1·K -1 -- cs Specific heat of PCM in liquid state, J·kg−1·K -1 -- DDH Discomfort degree hours, °C·h -- Hp Latent heat, kJ·kg−1 -- hout Convection coefficients over the exterior surfaces of the PCM panel, Wm−2·K -1 -- hin Convection coefficients over the interior surfaces of the PCM panel, Wm−2·K -1 -- k Thermal conductivity, Wm−1∙K−1 -- L Thickness, mm -- T Temperature, °C -- T0 Initial temperature of PCM panel, °C -- Tm Phase transition temperature, °C -- Tin Indoor air temperature, °C -- Tmax Maximum indoor air temperature, °C -- Tmin Minimum indoor air temperatures, °C -- Tout Outdoor air temperature, °C -- Tp, in Inner surface temperatures of PCM panel, °C -- Tp, out Outer surface temperatures of PCM panel, °C -- t Time, h -- x Direction of thickness, mm -- ρ Density, kg·m−3 -- △DDHPCM Difference of discomfort degree hours, °C·h -- △T Phase transition temperature interval, °C; Unsteady heat transfer numerical model -- PCM panel -- Passive solar building -- Indoor thermal environment -- Heating energy consumption; Energy storage -- Periodicals; Energy storage -- Research -- Periodicals; 621.3126
• DOI: 10.1016/j.est.2022.105019
• Languages: English
• ISSNs: 2352-152X

Abstract

Abstract: In this study, an unsteady heat transport numerical model of phase change material (PCM) panel under indoor-outdoor dual thermal disturbance conditions was development by using the apparent heat capacity method, which was employed to evaluate the effect of thermal performance parameters of PCM on the heat storage and temperature regulation capability of PCM panel. Then, a single-space passive solar building located in Tibet was used as a basic building model to study the influence of thermo-physical parameters, such as phase change temperature, thickness and position of PCM panel in composite wall on indoor thermal environment. Meanwhile, the indoor discomfort degree hours and heating energy consumption of the passive solar building with composite wall containing PCM panel were quantitatively analyzed, and the dynamic payback period of PCM investment in Tibet was calculated for economic analysis. The results indicated that the phase transition temperature, thickness and position of PCM panel have a significant impact on its heat storage and temperature regulation capability, and the composite wall containing PCM panel with reasonable thermo-physical parameters could obviously damp indoor air temperature fluctuation and save the building heating energy consumption. Compared with the basic building, applying a 30 mm thickness PCM panel with phase transition temperature of 18 °C on the interior side of the composite wall could reduce indoor discomfort degree hours in studied period (Dec. 20 to Dec. 24) by 74.9% and reduce heating energy consumption in the whole heating period (Dec. 01 to Mar. 01) by 20.76%, respectively. Furthermore, the economic analysis results show that the application of PCM panels in passive solar buildings in Tibet has high economic value, and the dynamic payback period of PCM investment in Tibet with 3% discount rate is 41.29 years, which is lower than the usual service life of a building. Highlights: Influencing factors are parametrically investigated for PCM panel. Indoor thermal environment of a single-space passive solar building with PCM panel was numerically simulated. Composite wall containing PCM panel produced heat storage and temperature regulation in passive solar buildings. UP to 20.76% reduction of heating energy consumption during the heating period of building can be achieved. The dynamic payback period of PCM investment in Tibet with 3% discount rate is 41.29 years.