| With the rapid development of society,building energy consumption is becoming an increasingly significant contributor to urban energy consumption.In particular,in northern China,a substantial portion of building energy consumption is attributed to the need for space heating during the winter season.The current heating regulation methods,such as climate compensation,still need improvement to avoid room overheating and reduce energy consumption.To achieve this,this dissertation investigates and analyzes the current situation of heating operation of residential buildings in Weifang area,and simulates the load of typical cases using DeST simulation software.Based on the load simulation results,the influence of outdoor temperature and solar radiation on space heating loads is studied.Based on heating load forecasting model,a climate compensation model considering solar radiation was developed and tested for its energy-saving effect.It is necessary to understand the basic parameters of the existing buildings and the heating status of the heat exchange stations in order to energy-saving renovation of existing buildings.This dissertation selects 178 heat exchanger stations in Weifang area as the study cases and identifies four key factors that affects building heating energy consumption:the thermal insulation characteristics of the building,the ratio of southward window to wall,the type of space terminal equipment,and the height of a building.Based on these factors,the study cases are divided into 16 typical buildings.Through on-site investigations and analysis on the operation status of the heat exchange station and the current situation of building energy consumption,it is found that the heating energy consumption of the existing buildings ranges from 43.67 to 122.71(k W·h)/(m~2·a),which is generally higher than the building energy saving standard,indicating potential of energy saving.Based on the physical information of buildings investigated,the annual dynamic load simulation models of 16 typical buildings with and without solar radiation are respectively established by using DeST energy consumption simulation software.Compared with the load forecasting model that only considers outdoor daily average temperature,this model more comprehensively considers the response of the building body’s thermal inertia to outdoor air temperature fluctuations and solar radiation.Based on the models,the heating loads of the 16typical buildings under different climatic conditions are simulated.The simulation results show that the model considering only the influence of outdoor air temperature predicts higher peak heating loads(with a maximum degree of 10.6%)and cumulative heating load(with a maximum degree of 22.3%)compared with the model comprehensively considers the outdoor air temperature fluctuations and solar radiation.The building thermal insulation,southward window-to-wall ratio and occupancy rate have subsequent influences on the results of heating load simulation,while the building height has relatively little influence on the load simulation results.Based on the influence of outdoor air temperature and solar radiation on the space heating load,the dissertation developed the fitted hourly heat load forecasting models of 16 typical buildings.Instead of considering the outdoor daily air average temperature only,this model comprehensively considers the response of the thermal inertia of the building envelope and solar radiation.According to the fitted hourly load forecasting model developed for the 16typical buildings,a dynamic climate compensation model considering solar radiation and hourly outdoor temperature is established.The climate compensation model uses building design parameters as references.However,considering the operating parameters of the heating station in the coldest period often deviate greatly from the design parameters,the design supply and return water temperature of typical buildings is determined based on the measured heat consumption and outdoor meteorological parameters,and are used as the reference parameters of the climate compensation model.Finally,the dynamic climate compensation model is applied to the heating operation of the actual project.A typical building is selected to analyze the operation effects of three modes:1)only considering the outdoor daily average temperature,2)considering the outdoor daily average temperature and the daily fluctuation of outdoor temperature,3)considering the outdoor average temperature,daily fluctuation and solar radiation.The results show that the average water supply temperature considering the daily fluctuation of outdoor temperature can be reduced by 2.11℃,the average water supply temperature considering solar radiation can be reduced by 4.09℃,and the average water supply temperature considering the daily fluctuation of outdoor temperature and solar radiation can be reduced by 6.21℃.The water supply temperature of the secondary network optimized by the improved climate compensation model can not only effectively respond to the hourly change of outdoor temperature,but also significantly reduce the energy consumption of space heating.The improved climate compensation model considering solar radiation and outdoor hourly temperature proposed in this dissertation shows good performance on heating operation regulation,which can meet the demand of indoor heating while achieving the purpose of energy saving and emission reduction. |
