齿型迷宫流道灌水器水力性能数值模拟研究

【目的】定量探究流道结构参数与灌水器水力性能之间的互馈关系。【方法】研究齿角度(a)、齿底距(b)、齿高度(c)和流道深度(d)4个关键因素,选用L18(37)正交试验设计方案,通过室内测试与数值模拟,定量分析了流道结构参数对其水力性能的影响。【结果】采用四面体含边界层网格或混合多面体网格的模拟精度最高,采用标准k-ε计算模型,流量偏差率可控制在6.00%的误差范围内,可推荐作为齿型流道结构灌水器数值模拟时的参考设置模式;按显著性水平α=0.1检验,流道深度和齿高度对流态指数存在显著影响;此外,研究构建了流态指数与齿型灌水器关键结构参数之间的定量多元线性回归方程为;X=4.67×10-4a-0.005 4b-0.016 1c+0.041 7d+0.442 2,流量系数的回归方程为:K=0.211 1a+2.822 4b+1.796 5c+8.247 8d-11.584 9。【结论】齿型流道结构滴头的网格划分宜采用四面体含边界层网格或混合多面体网格型式,且流态指数和流量系数与齿型灌水器关键结构参数之间的关系可以通过多元线性回归方程表示。

Numerical Simulation of Hydraulic Performance of Tooth-form Channel of Labyrinth Emitter

【Objective】The aim of the paper is to quantify the relationship between channel structure parameters and hydraulic performance of labyrinth emitter.【Method】Four factors, including dentation angle, bottom space between the dentations, dentation height and depth of flow passage were selected for the orthogonal experiment arrangement. Based on laboratory test and numerical simulation, we elucidated the influence of structure parameters on the hydraulic performance.【Result】Tetrahedral mesh with boundary layer mesh and mixing polyhedral mesh was most accurate. The error of simulated flow rate could be controlled around 6.00% using the standard k-ε model. Both depth of flow passage and the dentation height had significant influence on emitter discharge exponent(α=0.1). We derived regression models to describe the relationship between emitter discharge exponent and structural parameters of the flow passage, as well as the relationship between the discharge coefficient and structural parameters of flow passage.【Conclusion】This study determined the meshing pattern of the emitter and established the relationship between the structural parameters of the flow channel and its hydraulic performance.