摘要
地铁车厢空间狭小相对封闭,客室流场对乘客乘坐感受至关重要,已有地铁列车通过加装幅流风机改善车厢气流组织,但未对幅流风机改善流场效果做定量分析。本文通过CFD数值模拟列车在夏季温度35℃时的运行工况,分别研究了20℃送风时无风机和有风机作用下客室流场情况,以及研究在有风机运行时将送风温度提高到23℃时的客室流场。结果表明幅流风机能减小客室温度不均匀度,将无风机作用下的不均匀度0.49减小到有风机作用下的0.28;若适当提高空调出风温度,可以改善客室PMV指标,同时减小空调机组负荷。
The metro carriage is comparatively crowded and sealed, so the flow distribution of the carriage is important to passengers’ feeling. There are trains equipped with cross-flow fans for improving flow distribution, but no numerical analysis about the influence of fans had been done. In this passage, the CFD simulation is used to analyze cabin flow distribution when train is in 35℃ air environment.Whether cross-flow fans with swinging volutes are functional or not to carriage environment when supply air temperature is 20℃, and the flow distribution with cross-flow fans when supply air temperature is 23℃ are analyzed in this passage. And the final results indicate that cross-flow fans with swinging volutes can improve the temperature homogeneity, making temperature heterogeneous degree decrease from 0.49 to 0.28. If the supply air temperature is raised, the thermal comfort of carriage will improve as well as save energy.
关键词
幅流风机
客室流场
不均匀度
节能
cross-flow fan
cabin flow distribution
heterogeneous degree
save energy
