Study on Fluid Movement Characteristics inside the Emitter Flow Path of Drip Irrigation System Using the Yellow River Water

• Main Authors: Ji Feng, Weinan Wang, Haisheng Liu
• Format: Article
• Language: English
• Published: MDPI AG 2020-02-01
• Series: Sustainability
• Subjects: water sustainability; drip irrigation; yellow river water; emitter; flow characteristics
• Online Access: https://www.mdpi.com/2071-1050/12/4/1319

Vigorously developing efficient water-saving agricultural technologies using the Yellow River Water is an important way to achieve sustainable use of water resources. In order to clarify the fluid movement characteristics inside the flow path of the emitter under complicated water quality conditions in a drip irrigation system using the Yellow River Water, the optimal simulation turbulence model for the flow field in the flow path of the emitter was determined by comparing the macroscopic hydraulic characteristics with the microscopic fluid motion characteristics of the fluid in the emitter. On this basis, the two-phase flow model was used to calculate and analyze the characteristics of water flow movement and particle transport in the emitter. The results show that the RNG (Re- normalization group) <i>k-&#949;</i> turbulence model was the most suitable for the simulation of the flow field in the emitter, considering the macroscopic hydraulic performance and microscopic anti-clogging ability of the emitter synthetically, and both the comprehensive calculation accuracy and the calculation efficiency. The pressure showed a step-like uniform decrease along the direction of water flow. The fluid flow showed the regional movement characteristics of the mainstream and non-mainstream regions. The energy dissipation mainly occurred at the sudden change sites of the flow path structure. The particle phase velocity was slightly lower than that of the water phase. The velocity at the near-wall surface was relatively lower than that at the center, and the velocity distribution along the depth direction of the flow path was relatively uneven. The sediment was mainly deposited in the first half of the flow path. This study can provide a theoretical basis for solving the emitter clogging in the drip irrigation systems applying water from the Yellow River.