Pressure-compensating (PC) emitters are extensively utilized because they can enhance the irrigation uniformity and the terrain adaptability of drip irrigation systems. To examine the interaction between the elastic diaphragm and fluid of PC emitters, the internal flow behaviour and the diaphragm deformation of PC emitters were studied by one-way and two-way fluid–structure interaction (FSI) numerical simulation methods. The deformation characteristics of the elastic diaphragm, the change of the outflow section around the outlet of the pressure-compensating chamber, and the pressure and velocity distribution of the flow field were analysed in this study. The results illustrate that the deformation process of an elastic diaphragm during the entire working process could be divided into three phases: rapid deformation, slow deformation, and long-term tiny deformation. After the diaphragm contacted convex land, the overflow groove was the only channel where water could flow out of the PC emitters; and as working pressure increased, the increment of the diaphragm deformation was extremely tiny. However, it was the tiny deformation of the elastic diaphragm that maintained the flow rate of the PC emitters constant over a wide range of working pressures. The results can provide references for exploring the pressure-compensating mechanism of PC emitters and their optimal design.

中文翻译：

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压力补偿式滴灌灌水器的流动特性和隔膜变形*

压力补偿（PC）发射器被广泛使用，因为它们可以提高滴灌系统的灌溉均匀性和地形适应性。为了研究 PC 发射器的弹性隔膜与流体之间的相互作用，采用单向和双向流固耦合 (FSI) 数值模拟方法研究了 PC 发射器的内部流动行为和隔膜变形。本研究分析了弹性隔膜的变形特性、压力补偿室出口周围流出截面的变化以及流场的压力和速度分布。结果表明，弹性隔膜在整个工作过程中的变形过程可分为三个阶段：快速变形、缓慢变形、和长期微小的变形。膜片接触凸台后，溢流槽是水从PC发射器流出的唯一通道；并且随着工作压力的增加，膜片变形的增量极小。然而，正是弹性隔膜的微小变形使 PC 发射器的流量在很宽的工作压力范围内保持恒定。研究结果可为探索PC发射器的压力补偿机制及其优化设计提供参考。正是弹性隔膜的微小变形使 PC 发射器的流量在很宽的工作压力范围内保持恒定。研究结果可为探索PC发射器的压力补偿机制及其优化设计提供参考。正是弹性隔膜的微小变形使 PC 发射器的流量在很宽的工作压力范围内保持恒定。研究结果可为探索PC发射器的压力补偿机制及其优化设计提供参考。