| 摘要: |
| 【目的】研究新型果树根灌器螺旋对冲流道参数对水力性能的影响。【方法】采用单因素和响应面试验方法，研究螺旋对冲流道主要影响因素及其对计流量变异系数Cq的影响，建立并验证了不同压力区间Cq的回归模型，在不同压力区间以Cq最小为优化目标进行流道参数优化。【结果】引起Cq变化的主要参数为流道宽b、分流角α及流道单元数n，弯道直段长l1、弯道半径r、汇流段长l2对其的影响可忽略不计。α、b、n对Cq的影响存在交互作用，Cq随α、b、n的增加均呈先减后增趋势，响应曲面均存在极小值。低压区及高压区的Cq与α、b、n存在显著的二次函数关系，其二次回归模型复相关系数（R2）分别为0.996 7、0.997 1，与调整后的复相关系数（Adj R2）差值均小于0.2。优化得到高压区最优方案的Cq要小于低压区，2个压力区优化方案Cq预测值与实测值相对误差分别为2.8%、2.3%。【结论】用Cq回归模型对设计流量变异系数预测的精度可靠，螺旋对冲流道在高压区的灌水效果要优于低压区，且Cq优化的结果可靠。 |
| 关键词: 果树根部灌水器；螺旋对冲流道；几何参数；水力性能；响应面法 |
| DOI：10.13522/j.cnki.ggps.2022157 |
| 分类号: |
| 基金项目: |
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| Optimizing Geometrical Parameters of the Flow Channel in the Root-irrigation Emitters |
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ZHANG Jun, LI Lin
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1. College of Hydraulic and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, China;
2. Xinjiang Institute of Technology, Aksu 843000, China;
3. Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Urumqi 830052, China
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| Abstract: |
| 【Objective】The study is to present a new root-zone irrigation emitter and investigate the influence of the geometrical parameter of its spiral-hedge flow channel on hydraulic performance of the emitter. 【Method】The assessment is based on the variation coefficient of the design flow (Cq). Using single factor and the response surface test method, we studied experimentally how design parameters of the helical hedge flow channel affect Cq. We then established and verified a regression model to calculate the variation of Cq with operating and design parameters, from which we proposed how to optimize the flow channel parameters with minimizing Cq as the optimization objective. 【Result】The design parameters that affect Cq most are flow channel width b , the shunt angle α and number of flow channel units n. In contrast, the effect of straight section length l1, the bend radius r and the convergence section length l2 is negligible. The effect of α, b and n on Cq is confounding. With the increase in α, b and n, Cq decreases first and then increases once it reaches the minimal value. Cq varies with α, b quadratically when the operating water pressure was low or high, with their associated correlation coefficient (R2) being 0.996 7 and 0.997 1 respectively. The difference between the adjusted correlation coefficients is less than 0.2. The Cq obtained from the optimal solution for the high operating water pressure is smaller than that for the low pressure, and the relative errors between the predicted and measured Cq for the two pressure zones are 2.8% and 2.3%, respectively.【Conclusion】The regression model for variation of Cq with operating and design parameters is reliable, and the spiral hedge flow channel works better under high water pressure than under low water pressure. |
| Key words: root emitter for fruit trees; spiral hedge flow channel; geometrical parameter; hydraulic performance; response surface method |
