Research On Train Operation Safty Under Strong Side Wind

Serious accidents such as train capsizing always happened in special areas such as large bridge and high embankment and railway line in wind region under strong side wind. It is significantly important to ensure the safety of railway transportation by researching on the train operation safety under strong side wind and by finding the mechanism of train capsizing under strong side wind and at the same time by finding the solid protecting measurement.Start from researching the train aerodynamic under the situation that wind speed and train speed and railway line and vehicle coupled together, set up the math model of train capsizing on rail and model of carboy capsizing on bogie when train bearing transmit load or steady load, and get the relation between wind speed and critical train speed when train in different load condition and different railway situation. Based on the method related above, a method system on train safety has been set up fully under the situation that wind and train and railway line coupling together.Math model of train capsizing on track and carboy capsizing on bogie bearing transmit load or steady load has been built systematically and fully when train using different structure bogie, such as one suspension or two suspensions , steel spring or air spring, pendulum bogie or normal bogie, with or without shaker. The results show that the probability of capsizing is large when train bearing transmit load, and that train's capsizing not only relate to loads train bearing but also relate to relatively location of bogie and carboy. If the relative displacement between bogie and carboy is smaller, the train will be hard to capsize.Train aerodynamic performance is gotten. The results show that: aerodynamic forces of train bearing increase when wind speed or train speed increasing and that when wind angle is near 90 degree the aerodynamic forces are largest. In the same situation (wind speed and train speed and wind angle) aerodynamic forces improve with the increasing of height of bridge or embankment, structure of windward surface of embankment effect lightly to train's aerodynamic performance while structure of leeward surface effects significantly to train aerodynamic performance and train's aerodynamic forces decrease significantly when slope of leeward surface of embankment improves. To train in bridge in gorge train aerodynamic forces improve if the distance between the two hills decreases at the same wind speed.The limit value of train critical speed under the situation is gotten when wind speed and vehicle and railway line coupled together. Results as follow: the figure of box car and container car is almost not streamlined and they will bear large aerodyne forces and so the train critical speed is lower, while the figure of tank car is better waterline and it will bear little aerodynamic force at the same wind speed, so train's critical speed is higher. Train critical speed will decrease when height of bridge and embankment improves while the train critical speed can be improved if installing wind fence in railway line to decreasing the aerodynamic force, train critical speed will decrease sharply when train is running in curve line for the huge centrifugal force. Higher the center of gravity of train and higher the capsizing moment in same centrifugal force and which will decrease train critical speed. Lateral inertia force has significant influence to the whole system and installing dampers in bogie and reforming tread figure can effectively slow down the frequency and range of lateral vibration and can slow down acceleration of lateral vibration which will improve train critical speed. Based on the results of a single car, a speed limiting law of a train is put forward at last that the limiting speed value is the smallest train critical speed of the whole train in all dangerous point and the smallest train critical speed of all the single train.The reformed measurement is put forward to ensure train operation safety. To the train, decreasing its height of center of gravity and minimizing its lateral vibrating acceleration when in operation can improve train critical speed under strong side wind. But fundamentality speaking, reducing the aerodynamic force under strong side wind can improve train speed significantly, and the main measurements is to reform the train's figure and to set up wind fence in railway line. Taking box car for example the best aerodynamic figure of side wall and ceiling is given when train bearing strong side wind. Put forward the optimization parameters of all the types of wind fence in embankment. Put forward the optimization parameters such as height of wind fence and wind leaking ratio and its location of single side wind fence in bridge.The prediction model of wind speed is put forward in wind region. Pointing to the initial wind speed time serial, the first step is to average the initial data using moving average model, then get the true data using Kalman filter, the last is to built the wind prediction model using wind data serial or Neural Networks. Wind speed data serial prediction model is mainly pointing to the single point and predictes well and can also give the prediction error but need much more history data. Pointing to adjacent measurement points whose wind speeds correlating strongly, Neural Networks prediction model can be used which considers the nonlinear of the whole system fully and can give precious precision only using little history data.