Study On Simplified Calculation Method Of Heat Transfer In Passive House With Attached Sunspace

Passive House with attached sunspace is wide used in Chinese solar enrichment area,due to the influence of the double fluctuation of outdoor air temperature and solar radiation,the thermal load of the passive room with attached sunspace fluctuates greatly,the traditional steady-state algorithm is difficult to satisfy the requirements of calculation accuracy,and the dynamic algorithm is needed.And the scientific simulation software like De ST,Energyplus,Trnsys and other simulation software.is difficult to be widely applied in the field of engineering because of the difficult in using it and complex of modeling process.Based on this,this study established the attached sunspace between passive building heat transfer model,analyzes the attached sunspace between passive building thermal load,retaining structure is studied in the rule of variation of parameters on the heat transfer,passive building thermal load simplified calculation method is proposed,and developed a suitable for the use of dynamic load calculation software engineering designers.The main research contents and conclusions are as follows:(1)The heat transfer process of passive room is analyzed and the mathematical model of heat transfer of passive room with additional sunshine is established.On the premise of ignoring the mutual radiation of the inner surface,the heat consumption of the passive building foundation with additional sunlight can be divided into passive parts,heavy walls,doors and Windows,and cold air penetration;the heat transfer mathematical models for each heat transfer process were established respectively.Based on the periodic response coefficient,the heat transfer mathematical models for passive parts with attached sunspace and heavy wall were established.Based on the time-by-hour steadystate thermal process,the mathematical model of heat transfer of doors and windows was established.Based on the process of cold air osmotic heat transfer,a mathematical model of cold air osmotic heat transfer is established.The simplified calculation of the heat transfer between the passive parts and the heat transfer between the non-southward heavy mass structure is the focus of this research.(2)The influence law of wall structure on heat transfer of heavy wall under different meteorological conditions is analyzed,and a simplified calculation model of heat transfer of heavy wall by heat load coefficient method is proposed.By heavy structure cycle reaction coefficient of heat transfer model,analyzed the palisade structure under different meteorological conditions and facing to the heavy structure the influence law of heat transfer,and then presents the method of heat load coefficient of heavy structural heat transfer calculation,coefficient of heat load calculation model is established,according to the city-structure-orientation the data structure of the coefficient of heat load calculation results are presented.(3)The variation law of heat transfer between additional sunlight and key structural parameters is simulated and analyzed,and a simplified calculation model of heat transfer between additional sunlight is proposed.Based on the model of additional inter-sunshine heat transfer,the relationship between additional inter-sunshine heat transfer and structural parameters such as depth,window/wall ratio is simulated and analyzed.A simplified calculation method of additional inter-sunshine heat transfer based on the coefficient of change of heat transfer between public walls and the coefficient of change of air temperature between sunlight is proposed.The results show that the change coefficient of heat transfer and the change coefficient of air temperature between sunlight on the public wall are only related to the area and the type of the enclosure,which are unique to the location and the enclosure.And then set up a typical urban key structure parameters and the common wall heat transfer between the sun and the air temperature of empirical model,is put forward to change the wall heat transfer coefficient of common wall heat transfer experience model calculation simplified calculation model of heat transfer coefficient of change between the attached sunspace’s air temperature between air temperature experience model calculation between air temperature further to the sun heat transfer between air temperature calculation public wall interior public wall interior heat transmission simplified calculation model.(4)Combined with the simplified calculation models of door,window,cold air penetration,heavy structure and passive structure,a simplified calculation method of passive house thermal load was formed.The accuracy of the simplified calculation method was verified by using engineering data,and a thermal load calculation software for passive house was further developed.In order to verify the accuracy of the method,a physical heat transfer model of the passive room with additional sunlight was established to calculate the heat load of the passive room.The results were compared with those of the simplified model.The results show that the simplified calculation method proposed in this study can accurately calculate the heat load of the passive room.Combined with the simplified calculation model of heat transfer of heat collection and storage wall,the thermal load calculation software of passive room is developed by using C# language.The actual engineering test results show that the calculation of the software is less than10%,which meets the engineering design requirements.