铁路空调客车负荷的确定

Determination of Air-conditioner Load on Passenger Train

铁路空调客车的负荷是按铁道部部标准 (TB1 951 87) ,用稳定传热方法计算的 ,虽然计算过程简单 ,但计算出的负荷值要高于客车运行时实际出现的最大负荷值 ,而据此设计出的空调机组不利于节能。针对铁路空调客车行驶时易受外界影响 ,负荷变化快的特点 ,提出了利用非稳定计算法计算车体的逐时传热负荷。并以长途硬座客车为例 ,用上述两种方法对其负荷进行了计算。通过计算分析认为 :根据动态负荷的最大值可设计出满足实际需要的空调机组 ,计算出来的客车空调逐时负荷 (动态负荷 )更符合实际情况 ,并且能达到节能的目的 ,如果铁路客车空调应用变频自控技术 ,就可以根据动态负荷的变化情况自动调节制冷机的制冷量 ,可使机组的运行工况随着车内的负荷变化而变化 。

As required by the MOR standard (TB1951-8 7) , the air-conditioner load of a passenger train is calculated with steady heat transmission calculation method. However the load calculated is greater than the real maximum load of the train in actual operation, though the process of the c alculation is simple. So air-conditioners thus designed is not favorable for en ergy saving. Air conditioners on a running train are subject to external influen ce and swift changes. With that understanding, the paper proposes to use the uns teady calculation method to calculate heat-transmission load of the car body. T he load of a long-distance train with semi-cushioned seats is taken as the exa mple,and two methods are used for this calculation. The calculation and analysi s proves that the maximum dynamic load can be designed as such that it can actua lly meet the requirement of the conditioner. The calculated hourly load (dynamic load) is more realistic and saves energy. If frequency conversion and automatic control technology are used in passenger train air-conditioning, the condition ing capacity can be automatically regulated according to the change of the dynam ic load. So the operation of the conditioner can vary with the load. The purpose of saving energy is met.