Research On Flow Performance Of Solar Heating System Based On TRNSYS

With the rapid economic growth,people’s demand for a better life is getting higher and higher.The focus of most people has shifted to the comfort of the living environment.Creating a comfortable environment must be at the cost of energy consumption.There are abundant solar energy sources in northern China,with long heating periods and huge energy consumption.The solar heating system can meet the heating demand,save energy,gradually attract people’s attention,and become an important scientific research field.At present,the following bottleneck problems exist in the operation of solar heating:first,the flow coupling relationship of each loop in the heating system is complex,and the flow relationship is not clear,resulting in low heat utilization;second,the system hydraulic imbalance causes poor indoor heating effect and thermal comfort The performance is low and energy saving cannot be achieved.The work of this article includes:First,based on the solar heating system experiment platform,the structure,principles,parameters,etc.of each part of the system are explained;Second,establish a simulation model.Combined with the experimental platform and thermodynamic principles,mathematics such as heat collectors,hot water storage tanks,heating pipes,circulating water pumps,indoor temperature,flow control valves,fan coils,collector side and load side control,indoor temperature,PMV,etc.were built.Model,to provide theoretical support for the TRNSYS model of the heating system;third,the analysis of results.Analyze the simulated and experimental values of the outlet temperature of the hot water storage tank and collector,indoor and outdoor temperatures,system collection/heating flow,verify the rationality of the TRNSYS model,and lay the foundation for the dynamic analysis of flow and system thermal performance in Chapter 5Foundation;Finally,the system flow performance research.Through the analysis of the experimental results,it is concluded that the fitting curves of the simulation data and the experimental data are basically consistent,which proves that the TRNSYS model is correct and can be used as a model for the solar heating system flow performance research.The specific research contents are as follows:(1)Under typical meteorological conditions,the TRNSYS model was used to determine the optimal range of inclination and the selection of the optimal area for the collector of a building with an area of about 70 m~2;(2)Optimize the heat collection and heating flow values of the system.Compared with the initial operation of the system,the heat collection flow and heating flow values can be optimized to improve the thermal performance of the hot water storage tank and the heat utilization of the collector The research results show that the system’s daily heat collection efficiency is increased by 19.72%;the daily effective heat gain of the collector increases by 31.7 kWh;(3)The TRNSYS model was used to analyze the effect of hydraulic loss scheduling on indoor thermal performance and energy consumption of auxiliary heating equipment.Studies have shown that reasonable heat supply flow rate selection can meet user indoor needs and reduce energy consumption.5%,the daily power consumption of auxiliary equipment is reduced by 56 kWh;(4)Taking indoor thermal comfort(PMV-PPD)as the evaluation index,the influence of the heat collection and heating flow values on it was analyzed,and it was concluded that the heat supply side flow had a significant effect on the PMV and PPD values,and reasonable heat collection and supply The heat flow meets the requirements of ISO7730 indoor thermal comfort and meets the needs of users.The research results of this paper can be used for reference to improve the practical application of solar heating technology in China’s civil buildings.