Numerical simulation of different types of rural drainage pipeline with small diameter in plain river network area
ZHOU Liangjie1,2,, ZHENG Tianlong1,2,,, LIU Junxin1,2 1.Department of Water Pollution Control Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2.University of Chinese Academy of Sciences, Beijing 100049, China
Abstract:The discharge of rural sewage without effective treatment leads to the pollution of the rural environment. At present, most rural areas in China lack a complete sewage collection system. In rural areas where sewer systems have been laid, there were some problems such as the design of the pipe network not matching the characteristics of rural drainage, and too high construction funding of sewer systems. In order to solve these problems, the construction of sewer system with small diameter in rural area for sewage collection was proposed. The hydraulic characteristics for the rural sewer systems in the plains, hilly area and mountain area were explored, and the pipe segments were selected for numerical simulation. The results showed that the pressure change trend of part of the elbow was opposite to the velocity change trend, and the turbulent kinetic energy at the elbow was large; the design fullness of pipe in plain and hilly area was 0.3~0.9, and the design flow velocity was 0.7~0.9 m·s?1. The design fullness of pipe in mountain area was 0.1~0.3, and the design flow velocity was about 1 m·s?1. Research above enriched the understanding of the flow patterns of sewer systems with small diameter and provided a reference basis for more reasonable design of rural sewers and prediction of sites where risk will appear. Key words:plain river network area/ characteristics of rural drainage/ drainage pipe with small diameter/ multiphase flow model/ numerical simulation.
图1模型整体网格及边界层网格 Figure1.Global and boundary layer mesh of the model
ANSYS Inc. ANSYS Fluent Theory Guide[M]. Canonsburg, PA: ANSYS, Inc., 2018.
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1.Department of Water Pollution Control Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China 2.University of Chinese Academy of Sciences, Beijing 100049, China Received Date: 2020-01-10 Accepted Date: 2020-03-07 Available Online: 2020-11-11 Keywords:plain river network area/ characteristics of rural drainage/ drainage pipe with small diameter/ multiphase flow model/ numerical simulation Abstract:The discharge of rural sewage without effective treatment leads to the pollution of the rural environment. At present, most rural areas in China lack a complete sewage collection system. In rural areas where sewer systems have been laid, there were some problems such as the design of the pipe network not matching the characteristics of rural drainage, and too high construction funding of sewer systems. In order to solve these problems, the construction of sewer system with small diameter in rural area for sewage collection was proposed. The hydraulic characteristics for the rural sewer systems in the plains, hilly area and mountain area were explored, and the pipe segments were selected for numerical simulation. The results showed that the pressure change trend of part of the elbow was opposite to the velocity change trend, and the turbulent kinetic energy at the elbow was large; the design fullness of pipe in plain and hilly area was 0.3~0.9, and the design flow velocity was 0.7~0.9 m·s?1. The design fullness of pipe in mountain area was 0.1~0.3, and the design flow velocity was about 1 m·s?1. Research above enriched the understanding of the flow patterns of sewer systems with small diameter and provided a reference basis for more reasonable design of rural sewers and prediction of sites where risk will appear.
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