一个动态的单维模型,用于模拟污水管道中不稳定的空气-水分层流
Hao Le1, Biao Huang1, Chunling Wang2
1School of Civil and Environmental Engineering, Ningbo University, Ningbo 315200, Zhejiang, China.
概括
本研究提出了下水道通风的新数学模型,改进了空气流模拟,以更好地控制气味和压力. 该模型建立了空气到水流量和下水道填充比率之间的关键关系.
科学领域:
- 环境工程 环境工程
- 流体动力学 流体动力学
- 计算建模 计算建模
背景情况:
- 对于卫生和雨水下水道系统来说,有效的通风至关重要,以控制气味和压力激增.
- 现有的数值模型在实际应用中经常失败,原因是空气流模拟的局限性或仅适用于稳定状态条件.
研究的目的:
- 开发一个数学模型,准确模拟自然通风下下水道系统的运行条件.
- 在动态和复杂的现实世界下水道网络场景中解决当前模型的局限性.
主要方法:
- 模拟动态水流使用一个冲击捕获麦科马克方案.
- 开发了一种集成能量和动量方程的动态空气流模型,避免了代压力计算.
- 集成的接口摩擦系数来改进动量交换和空气压力解释.
主要成果:
- 该模型表现出适应复杂边界条件的适应性,适用于真实下水道网络空气流模型.
- 确定了空气到水流量比率和自然通风下的填充比率之间的直接相关性.
- 一个经验公式被推导出来表示这种已识别的关系.
结论:
- 开发的数学模型为模拟下水道系统中的自然通风提供了重大进步.
- 这些发现提供了实际的工程见解,特别是空气到水流量和填充比率的衍生实证公式.
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