基于密封缝隙非线性特性的车内外压力传递模型研究

Primary Study on Variation Law of Tightness and Dynamic Air Tightness Model of High-speed Train

根据静态气密性试验数据和理想气体绝热等熵假设,研究某型号高速列车在不同内外压差下的密封缝隙的非线性特性,结合密封缝隙的非线性特性建立车内外空气通过车体缝隙的质量流量与车体内外压力的关系,然后根据高速列车高静压风机特性曲线建立换气风机(新风机和废排风机)通风量的数学模型。并由质量守恒定律推出考虑密封缝隙非线性特性的车内外压力传递模型。列车运行过程中,车厢压力保护系统(即换气风机)需要根据瞬时的车内外压力环境做及时的调整,而这个动态响应过程需要一定的时间,故模型建立时考虑延迟时间。根据试验数据对模型进行修正,通过仿真验证了模型的可行性。

Based on the experimental data of static air tightness and adiabatic isentropic hypothesis of ideal gas,the non-linear characteristics of sealing gaps of a high-speed train under various internal and external pressure differences were studied.Combined with the non-linear characteristics of sealing gaps,the relationship between the mass flow of the air inside and outside vehicle body passing through the vehicle body gap and the pressure inside and outside the vehicle body was established,followed by the establishment of the mathematical model of the ventilator(new air fan and waste exhaust fan),according to the characteristic curve of high static pressure fan of a high speed train.Based on the law of conservation of mass,considering the nonlinear characteristics of the sealing gap,a model of pressure transfer inside and outside the vehicle was deduced.In the process of train operation,the pressure protection system(namely the ventilator)of the carriage needed to make timely adjustment according to the instantaneous pressure environment inside and outside the vehicle.Given a certain period of time the response process took,the time delay was considered when the model was built.The transfer model was modified with experimental data,and the feasibility of the model was verified via simulations.