青藏线环境条件对列车空调新风量的影响

Influence of environmental condition of Qingzang railway on the fresh air requirement of train air-conditioning

为研究外界气象条件对在高海拔缺氧地区运行的列车空调新风需求量的影响,以青藏铁路沿线实际气象参数和环境条件为基础,依据室内CO_2质量浓度平衡原理,计算弥散供氧方式下列车在不间地区的空调新风量调节值。结果表明,与选取固定室外温度(40℃)相比,选取极端最高温度时的新风量节约率最大值达5.37%。综合考虑高原列车车内正常人体生理循环所需氧浓度和良好的室内空气品质要求,提出了一种既能控制氧浓度又能保证室内污染物浓度不超标的确定空调新风量的新思路。本研究对青藏铁路列车空调系统的技术改进和运行管理提供了参考。

This paper is aimed at disclosing the relation between the particular climatic environmental condition of high altitude regions lacking of oxygen and the air-conditioning fresh air demand in the Qingzang railway passenger cars. As is known, the meteorological parameters and environmental condition of Qingzang railway are specific both at home and abroad. According to the meteorological parameters and environmental condition of Qingzang railway, we obtained the air-conditioning fresh air requirement for different regions under the system of dispersion-oxygen-supply the mechanism of CO2 quality balance. This paper calculated the fresh air requirement under the extreme highest temperature of each region classified by the altitude and the given outdoor temperature 40 ℃ for the whole railway line, respectively. The results of our study indicate that the air-conditioning fresh air requirement should be in conformity with the former than the latter. The maximum value for fresh air conservation rate can get up to 5.37% along the railway line, which is the key to the airconditioning system that fresh air needs to be pre-heated in the plateau area. And, in turn, for a plateau passenger car with oxygen- supply system, the less air-conditioning fresh air quantity is perhaps unable to lower the higher oxygen concentration level to the set scale; the more air-conditioning fresh air quantity may unable to ensure the necessary oxygen concentration level. But the accumulative pollutants in the air-conditioning compartment actually need more fresh air. Facing to this contradictory situation, this paper has brought about an improved method, which is expected to be able to ensure the oxygen concentration needed in supplying enough fresh air for the passen- gers. Thus, it can be seen that the given study is valuable for the improvement of the particular fresh air requirement both in technology and the actual running management for passenger cars traveling along the Qingzang railway line.