120阀内孔径对制动系统性能的影响

使用基于气体流动理论的列车制动系统数值仿真方法定量分析了120阀的紧急阀III孔径、局减阀上的局减孔孔径、加缓风缸向列车管充气孔孔径对单编万吨列车制动、缓解特性的影响.仿真结果表明:紧急阀III孔径对列车的紧急制动特性有明显的影响。该孔径在2.3～2.7 mm范围内能够保证在常用制动时不发生紧急作用,同时紧急作用也能正常发生,并且该孔径越大,其制动波速越慢,在紧急制动时,该孔径由2.35 mm增大到2.65 mm,其制动波速由283.2 m/s降低到244.2 m/s,降低了14.2%;局减阀上局减孔孔径对常用制动时的制动波速有明显的影响,孔径越大,其常用制动的制动波速越快,在减压100 kPa时,孔径为1.5 mm时比0.5 mm时制动波速增大了77.4%;加缓风缸向列车管充气孔的大小对缓解波速有明显的影响,该孔径越大,缓解波速越快,在减压100 kPa之后缓解的过程中,随着该孔径由0.5 mm增大到1.5 mm,缓解波速增大了53.1%,小减压量制动后缓解时,该孔径大小对缓解波速影响较小。该结论为新阀的设计提供了参考。

The effect of the 120 valve apeture to the brake system performance

The influence of emergency valve III hole,the local reduction valve hole,and the acceleration release cylinder hole to the train pipe on brake system characteristics was simulated with the train braking system numerical simulation method which based on air flow theory.The results show that the emergency valve III hole’s size has obvious influence to the emergency brake characteristic of train: the hole size in the range of(2.3 ~ 2.7) mm ensure the emergency application valve does not work in normal brake;the emergency valve III hole is bigger,its brake propagation speed is slower,the hole increases from 2.35 mm to 2.65 mm and its brake propagation speed changed from 283.6 m/s to 244.2 m/s,reduced by 14.2% when it works;the size of the local reduction holes has influence to the service application brake propagation speed,the bigger,the faster;the brake propagation speed increases 77.4% as the hole increases from 0.5 mm to 1.5 mm;the acceleration release cylinder to the train pipe has obvious influence to the release propagation speed,after releasing 100 kPa in breaking,as the hole increased from 0.5 mm to 1.5 mm,the release propagation speed increased by 53.1%,release after small amount of breaking,the hole size has little influence to the release propagation speed.This work will benefit the new valve design.