Modeling method of an active–passive ventilation wall with latent heat storage for evaluating its thermal properties in the solar greenhouse

• Published in: Energy and buildings Vol. 238; p. 110840
• Main Authors: Han, Fengtao, Chen, Chao, Hu, Qingling, He, Yipeng, Wei, Shen, Li, Caiyun
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 01.05.2021; Elsevier BV
• Subjects: Active–passive ventilation wall; Air temperature; Design; Design optimization; Design parameters; Energy balance; Energy consumption; Engineering application; Finite element method; Greenhouses; Heat; Heat storage; Indoor environments; Interpolation; Latent heat; Latent heat storage; Mathematical model; Mathematical models; Meteorological parameters; Modelling; Optimization; Phase change materials; Solar energy; Solar greenhouse; Solar power; Specific heat; Systems design; Thermal performance; Thermal properties; Thermodynamic properties; Ventilation; Winter; Engineering application; Active–passive ventilationwall; Mathematical model; Latent heat storage; Thermal performance; Solar greenhouse
• ISSN: 0378-7788; 1872-6178
• DOI: 10.1016/j.enbuild.2021.110840

•APVW-L’s model was validated against measured data with a high accuracy.•The model was used to define the rational parameters of the proposed wall.•A full-scale greenhouse with the proposed wall was built and tested in Beijing.•The proposed wall can store 5.36 MJ/(m2·day) of solar energy on a sunny day.•The proposed wall increased indoor air temperature by 0.8–1.4 ℃ aftermidnight. Active-passive phase change heat storage technologies have been obtained extensive application to decrease greenhouse’s demands for fossil energy during off-seasons. To develop the utilization ratio of solar energy in solar greenhouses during winter, the active–passive ventilation wall with latent heat storage (APVW-L) was introduced and could be integrated into greenhouse’s back-wall. However, system design and operation parameters are subjected to numerous factors, including its structure, material performance and outdoor meteorological parameters. To achieve optimization in the energy performance of this system, this study used finite element analysis and lumped parameter analysis to establish coupled energy balance equations of the APVW-L and the air inside vertical air passages, and the cubic spline interpolation was used to calculate the continuous relationship between phase change material’s equivalent specific heat capacity and temperature. This modeling method of the APVW-L was accurately validated against the measured data, and then used in the optimization design and operation strategy of the APVW-L in the greenhouses. This study demonstrated that the optimized APVW-L could store 5.36 MJ/(m2·day) of solar energy in Beijing. Compared to the identical conventional greenhouses, aftermidnight, the experimental greenhouse having APVW-L increased the back-wall’s interior surface temperature by 2.2–3.4 °C, and the average indoor air temperature by 0.8–1.4 °C. This study provides methods for the APVW-L's optimization design and its operation strategy, even for the rationalizationof the near-zero energy consumption of the solar greenhouse during winter.