To investigate the aerodynamic effects and dynamic airtight performance of the fast metro train designed for a speed of 120 km/h when running on the multi-section bridge and tunnel connection line,a full-scaled test was conducted.A sealed metro train was developedwith 4-car marshaling on a multi-section bridge and tunnel connecting subway express line in Wuhan.The testing system used LL-250-15A Kulite pressure sensor to measure the transient pressure changes outside and inside the train.The characteristics of pressure fluctuation outside the train were analyzed,and the amplitude of pressure variation at different measuring points along the train length were compared.The pressure comfort inside the train under different air conditioning conditions was analyzed.Proved by three same experimental tests,the experimental results were repeatable.The results show that when the train accelerates and decelerates in the tunnel section during the whole line operation,the amplitude of pressure variation outside the train is significantly larger than that in the elevated section.The worst aerodynamic effect occurs at the variable section of the air defense door in the underground section,when the train passes through this area in the up-line,the pressure outside the train changes by 1 071 Pa within any 3 seconds while it changes by 905 Pa within any 3 seconds in the down-line.Compared with the down line,the pressure fluctuation amplitude of any 3 seconds outside the train of up line is 18.3%larger.During the operation of the train,the pressure wave protection valve acts in response to severe pressure changes.When the air conditioning is on and the pressure wave protection valve is normally in operation,the pressure within any 3 seconds inside the train decreases by 16%in the up line and 28%in the down line compared with that when the pressure wave protection valve is open but not in operation.The air conditioning pressure wave protection valve can effectively reduce the influence of pressure fluctuation outside the train on the air pressure inside the train.The research results can provide reference for the design of fast metro line,the operation of metro train and the optimization of metro train air tightness.
关键词
地铁快线/桥隧衔接/实车试验/压力波/气密性
Key words
metro express line/bridge tunnel connection/full-scale test/pressure wave/airtight performance
维普
万方数据