市政供热有限空间通风防护技术数值模拟

发布时间：2018-03-02 18:22

本文选题：市政供热　切入点：有限空间　出处：《哈尔滨工业大学学报》2017年08期 　论文类型：期刊论文

【摘要】：为有效指导市政供热有限空间机械通风现场施工,保障作业人员安全,采用CFD方法对通风过程进行数值模拟计算,研究通风过程中有限空间内部流场、温度场、氧气体积分数、二氧化碳体积分数的分布规律.结果表明:进行机械通风时,相对于供热管沟,小室内新旧空气替换较快,温度下降及气体体积分数恢复都较为迅速;供热管沟内风流场受内部结构和热升力的影响,风流主要沿管沟底部流动,管沟顶部空气速度较小、温度较高、氧气和二氧化碳体积分数恢复较慢.针对所研究的管沟,通风量为6 000、8 000、10 000、12 000、14 000 m~3·h~(-1)时,最小通风时间应分别不小于45、32、22、15、10 min.实际作业中应以管沟中段顶部空气中的氧气体积分数作为衡量通风效果的关键参数.
[Abstract]:In order to effectively guide the field construction of mechanical ventilation in limited space of municipal heating and ensure the safety of operators, the ventilation process is numerically simulated and calculated by CFD method. The flow field, temperature field and oxygen volume fraction in finite space are studied in the process of ventilation. The results show that when mechanical ventilation is carried out, the old and new air is replaced quickly, the temperature drops and the volume fraction of gas recovers rapidly. The air flow field in the heating pipe ditch is affected by the internal structure and thermal lift. The air flow mainly flows along the bottom of the pipe ditch. The air velocity at the top of the pipe ditch is smaller, the temperature is higher, and the volume fraction of oxygen and carbon dioxide recovers slowly. The minimum ventilation time should be not less than 45 ~ 32t 22 ~ 1510 min when the ventilation rate is 6 000 ~ 8 000 ~ 10 000 m ~ (-1) ~ 14 000 m ~ (-1) 路h ~ (-1). In practice, the oxygen volume fraction in the top air of the middle section of the pipe trench should be taken as the key parameter to evaluate the ventilation effect.
【作者单位】：北京市劳动保护科学研究所;
【基金】：北京市自然科学基金(8152014) 北京市博士后科研活动经费资助项目(2016ZZ-82) 北京市科学技术研究院青年骨干资助项目(201407)
【分类号】：TU995

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