Study On The Anti-galloping Effectiveness Of Additional Conductor Interphase Spacers Of OCS In Strong Wind Area And The Structural Optimization Of Wind-break Wall

Lanzhou-Urumqi High-speed Railway via Lanzhou,Xining and Urumqi,with a total line length of 1,776 km.The five major wind areas along the high-speed railway route are frequently windy,with strong wind and instant destructive power,resulting in frequent train overturning,rollover and other accidents.Therefore,wind-break wall has been established along the railway.Although the construction of the wind-break wall has effectively improved the safety of train operation,it has intensified the galloping of the additional conductor of the overhead contact system(OCS),deepening the wear of the connecting hardware and leads,and easily caused wire breakage and discharge accidents.Therefore,it is necessary to carry out further research on the prevention and control of the galloping of the additional conductor.Firstly,a low-speed wind tunnel test is built based on the similarity ratio,the effectiveness and reliability of the model developed in this text are verified by combining the experimental measurements with the results obtained from numerical simulations.The fluid computational domain models are established for the cases without and with wind-break wall,and the changes of the flow field and aerodynamic characteristics around the positive feeder are analyzed with and without wind-break wall.The results indicate that the convergence of the wind-break wall on the airflow in the condition of the wall lead to an obvious increase in the positive feeder aerodynamic coefficient,which leads to an increase of the galloping of the positive feeder.Secondly,in view of the shortcomings of the wind-break wall along the Lanzhou-Urumqi high-speed railway in "preventing cars but not preventing nets".On the basis of the original wind-break wall,through the design of a perforated wind-break wall,the different opening models of the wind-break wall are established,and the grid is divided.The optimum porosity of the wind-break wall is determined by studying the flow field around the calculation area of the wind-break wall with different porosity and the change of wind speed and aerodynamic characteristics around the positive feeder.On this basis,the best porosity and opening angle of the wind-break wall are determined by further studying the change law of the aerodynamic characteristics of the positive feeder under different opening angles of the wind-break wall.The results show that the lift and drag coefficient of the positive feeder decrease obviously while taking into account the opening angle of the wind-break wall.Finally,the shape finding analysis is carried out by parabolic method and suspension chain line method,and the primary form of the additional conductors of the catenary are obtain by ANSYS Parametric Design Language after being loaded by their own weight and the installation of interphase spacer.The wind speed at the location of the additional conductor is obtained by numerical simulation with the WAWS method,and compare the vertical displacement,transverse displacement,displacement spectrum change and tension change of the additional conductor before and after the installation of the interphase spacer,then analyze the prevention effect of inter-phase spacer.The results show that after installing the interphase spacer anti-dance device,the additional conductor galloping displacement decreases significantly and the dynamic tension of the conductor decreases significantly,which proves the effectiveness of the interphase spacer anti-dance device.