Theoretical Analysis Of Heat Transfer Process Of Buildings Coupled With Solar Ventilation Interior Walls

The Solar Air Collector-Hollow Interior Wall Heating System is a heating technology that combines a solar air collector with a hollow ventilated inner wall.It uses the internal wall structure to store heat,and the heat collected by the solar air collector stored during the day is released at night.Air to the room to improve the indoor thermal environment at night.At present,most of the heating technologies that combine solar air collectors and heat storage technology use the external protection structure for heat storage,and the heat loss is large.The inner wall can be used as the heat storage structure to release all the stored heat into the room,thereby reducing Small heat loss.The heating effect and indoor thermal environment of the system depend on the thermal storage process and system control parameters of the internal wall.In this paper,the following research contents are carried out for the heat transfer process of the coupled solar hollow ventilated interior wall by theoretical analysis and simulation calculation:(1)The simulation model of the solar air collector is established,and the simulation results are processed by the dimensionless analysis and data fitting method to obtain a simplified calculation model of the solar air collector,which can greatly reduce the simulation.time.The comparison between the results of the simplified calculation model calculation and the experimental data in the literature shows that the simplified calculation model has higher precision,and the model can be used to evaluate the thermal performance of the solar air collector.(2)Using the thermoelectric analogy theory to establish a comprehensive RC network model for heat transfer between room air and enclosure structure in the system.The model considers the effects of cold wind infiltration,solar radiation and other factors.Thermal process parameters such as internal and external surface temperature and heat flux density of the structure.Comparing the model calculation results with the simulation results of EnergyPlus software,the wall wall error is 1.26 °C and the indoor air is 0.66 °C.The results show that the established integrated RC network model can effectively predict the temperature of each node in the room.(3)A mathematical model of the hollow ventilated interior wall is established,which couples the RC model of the inner wall section with the number of heat transfer units(NTUs)of the cavity section.The coupled heat transfer characteristics of the air and the inner wall in the cavity can be obtained by using the model.Compared with the experimental data,the temperature rise error of the inlet and outlet is 0.6 °C and the error rate is 3.4%,whichindicates that the coupling model can predict the exit temperature of the cavity well.(4)Coupling the first three parts of the model,the overall model of the Solar Air Collector-Hollow Interior Wall Heating System was established.The model is used to analyze the influence of internal thermal properties,interior wall thickness,solar air collector air volume and outdoor meteorological parameters on the internal wall heat storage and heat release process and indoor thermal environment.The results show that the interior wall materials with larger heat capacity have better heat storage and release performance;the thermal conductivity of interior wall materials is 0.6 ~ 1.4W /(m · K),the maximum temperature range is the largest in the room;the thickness of different interior wall materials The effect of heat storage and release on the inner wall is also different.The inner wall material with smaller heat capacity has the best thickness than the larger heat capacity.The optimal air volume of the collector is 150~200m3/h;the average temperature is higher.Urban solar air ventilated interior walls with stronger solar radiation increase the room temperature even more.