| 引用本文: | 胡贵荣,李诗莹,金嫣婧,等.扩散段中心轴偏移距离对非对称文丘里施肥器吸肥性能的影响[J].灌溉排水学报,2023,42(6):119-125. |
| HU Guirong,LI Shiying,JIN Yanjing,et al.扩散段中心轴偏移距离对非对称文丘里施肥器吸肥性能的影响[J].灌溉排水学报,2023,42(6):119-125. |
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| 摘要: |
| 【目的】提高非对称文丘里施肥器吸肥性能，探明吸肥性能、水力性能对扩散段中心轴偏移距离的响应关系。【方法】设计了5种不同扩散段中心轴偏移距离的非对称文丘里施肥器，分别对其进行吸肥性能试验与数值仿真，对比分析了其吸肥量、临界吸肥压差、进水口临界吸肥压力。【结果】非对称文丘里施肥器在正常工作阶段，吸肥量与进口压力呈良好的线性关系，临界吸肥压差和进水口临界吸肥压力均随出水口压力的增大而增大。与非对称文丘里施肥器原型（F1）相比，将扩散段设置为偏心向下的非对称文丘里施肥器（F5）的吸肥流量和吸肥效率分别提升13.03%~40.16%和12.09%~39.13%，随着进口压力值增大，增幅逐渐降低。当进出口压差在0.15 MPa左右，吸肥流量达到最大值，与F1施肥器相比，F5施肥器的最大吸肥流量提升13.03%，临界压差降低7.69%。【结论】正常工作时，降低出水口压力，有利于降低进水口吸肥临界压力；将扩散段向着远离吸肥管一侧移动，有利于降低局部水头损失，提高喉部负压利用效率，提升极限工况下吸肥流量，降低吸肥临界压差，提升文丘里施肥器整体工作性能。 |
| 关键词: 文丘里施肥器；扩散结构；吸肥性能；吸肥流量 |
| DOI：10.13522/j.cnki.ggps.2022587 |
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| Effect of Offset Distance of the Central Axis of Diffusion Section on Fertilizer Absorption of Asymmetric Venturi Injector |
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HU Guirong, LI Shiying, JIN Yanjing, CAO Yuan, WANG Zhenhua, LIU Ningning
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1. College of Water Conservancy & Architectural Engineering, Shihezi University, Shihezi 832000, China; 2. Key Laboratory of Modern Water-saving Irrigation of Xinjiang Production & Construction Group, Shihezi 832000, China; 3. Industrial Technology Institute of the Xinjiang Production and Construction Corps, Shihezi 832000, China; 4. Key Laboratory of Northwest Oasis Water-saving Agriculture, Ministry of Agriculture and Rural Affairs, PR China, Shihezi 832000, China
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| Abstract: |
| 【Objective】The asymmetric Venturi fertilizer injector is a device to simultaneously supply water and nutrients to crops through a drip irrigation system. Its performance is influenced by various factors. In this paper, we experimentally study the impact of the offset distance of the central axis in the diffusion section on fertilizer adsorption. 【Method】Five asymmetric Venturi injectors with different diffusion sections were studied. Their fertilizer absorption was experimentally and numerically studied. The fertilizer absorption rate, critical pressure difference and the critical pressure at the inlet for fertilizer absorption were compared and analyzed between the five injectors.【Result】Under normal working conditions, the fertilizer absorption rate linearly increased with the inlet pressure. When the pressure difference between the inlet and outlet was 0.15 MPa, the fertilizer absorption rate maximized. The critical pressure difference and critical inlet pressure both increased with the increase in the outlet pressure. Compared with original asymmetric Venturi injector (F1), the asymmetric Venturi injector with eccentric downward diffusion section (F5) increased fertilizer absorption rate and efficiency by 13.03%~40.16% and 12.09%~39.13%, respectively. The increase, however, gradually decreased with the increase in the inlet pressure. Compared with F1, F5 increased the maximum fertilizer absorption rate by up to 13.03% and reduced the critical pressure difference by 7.69%.【Conclusion】When working at normal conditions, reducing the outlet pressure was beneficial to reducing the critical pressure at the inlet for fertilizer absorption. Moving the diffusion section away from the side of the fertilizer suction pipe can reduce local water head loss, make pressure at the throat more negative, thereby increasing the flow rate of fertilizer into the injector and reducing the critical pressure difference for fertilizer absorption. Our findings can help improve the design of the Venturi fertilizer injector for drip irrigation-fertigation systems. |
| Key words: venturi injector; diffusion structure; fertilizer absorption performance; fertilizer absorption flow |
