中国电力

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供热蒸汽管道效率分析

李建锋   

  1. 中国电力企业联合会电力可靠性管理中心
  • 收稿日期:2017-06-20 修回日期:2018-07-02 出版日期:2018-08-21 发布日期:2018-08-21
  • 通讯作者: 李建锋

Exergy efficiency analysis of heating steam pipeline

  • Received:2017-06-20 Revised:2018-07-02 Online:2018-08-21 Published:2018-08-21

摘要: 为了探讨蒸汽管道的节能效果,建立了蒸汽管道内一维流动模型,计算了2km长度蒸汽管道的热效率及?效率。计算结果表明,在蒸汽流量不变时,随着管道内蒸汽流速的降低,管道的压力损失也随之降低,其热效率一直降低,但是?效率先增加后降低,有一最大值。当蒸汽流量在250t/h,并且管道?效率处于最大值时,蒸汽管道所节能的能量可以使汽轮机多输出约3330kW的电功率。当蒸汽流速低于25m/s时,管道压力损失及?效率变化幅度明显降低,因此,管道内蒸汽流速应该根据投资成本的大小在0~25m/s范围内合理选取。

关键词: 蒸汽管道, 蒸汽流速, 管道?效率, 管道热效率, 供热

Abstract: In order to investigate energy saving effect of steam pipe, a one - dimensional flow model in steam pipe was established, thermal efficiency and exergy efficiency of the 2km-long steam pipe were calculated. The calculation results show that when steam flow is constant, the pressure loss as well as thermal efficiency of the pipe decrease as long as steam flow rate in the pipeline is reduced, , whereas exergy efficiency increases at first and then decreases,thus a maximum value exists. When steam flow is 250 t/h and pipe exergy efficiency is at its maximum, energy saved by the steam pipe allows turbine to output more than about 3330 kW of electrical power. When steam flow rate is less than 25m/s, variation scope of pressure loss and exergy efficiency of pipeline are obviously reduced. Therefore, the steam flow rate in pipeline should be selected according to investment cost in the range of 0 ~ 25m/s.

Key words: steam pipe, steam flow rate, pipe exergy efficiency, pipe thermal efficiency, heating