Research On The Characteristics Of The Thermal Environment And Energy Performance Evaluation Method Of Underground Stations In Northern China

Owing to the continuous development of metro construction in northern China,the number of metro stations has also ushered in a period of rapid growth,which has resulted in a large amount of energy consumption.In order to realize the energy-saving operation of underground stations,it is essential to study the energy use characteristics and evaluation methods of these stations.However,since the underground station has a complex structure,the energy consumption of the station’s environmental control system is affected by various factors such as geographical climate and piston wind.Currently,there is still a lack of comprehensive and in-depth research on the actual conditions of the thermal and humid environment,methods to calculate the cooling load,and the evaluation of the energy performance of underground stations.Therefore,this article first studies the energy consumption characteristics and evaluation methods of the northern urban metro system,and then studies the characteristics of the thermal environment of the underground stations in summer,and analyzes the volume of the train-induced airflow in the station based on field measurement and theoretical calculation.On this basis,an improved algorithm for the cooling load calculation is proposed and,finally,an energy performance evaluation system for underground stations is established.The main work completed in the thesis is as follows:(1)Based on the historical energy consumption data of metro lines,a set of energy analysis methods for urban metro systems is proposed.Taking the Tianjin metro system as an example,the energy consumption status and characteristics of the system are studied by disaggregating the energy consumption data of the main energy-consuming items.The appropriate energy evaluation indicators are selected based on the correlation analysis of the factors affecting energy consumption.Finally,the indicators are used to analyze and compare the level of energy use of the metro system to help achieve a reasonable evaluation of the energy consumption of the urban metro system.(2)Based on field measurements of the summer thermal environment of underground stations initially operated in the north area,the characteristics of the thermal environment of the station are summarized,and it is found that airflow from the track area of the station during the initial operation stage can bring a cooling effect to the station.At the same time,the variation law of the train-induced airflow in the station and the waveform variation characteristics of the airflow volume under different traffic conditions are analyzed.Based on the above work,combined with the classification statistics of the stopping time interval of the up and down trains,an improved calculation method for the cooling load of the station is proposed,which provides a new scheme for accurate quantitative analysis of the impact of train-induced airflows on the cooling load of the station.(3)By studying the existing building energy efficiency labeling methods and relevant energy-saving regulations,and aiming at the energy consumption characteristics of underground stations and systems,a comprehensive evaluation system for the energy performance of underground stations is proposed.The system quantitatively evaluates the energy efficiency of underground stations from three aspects: the relative energy-saving rate of the station,the system energy efficiency indicators,and the application of energy-saving technologies.The case study shows that the evaluation system provides the energy benchmarks for the underground station and its system,which lays a foundation for the evaluation of the energy performance of underground stations.