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C_(q)的影响,建立并验证了不同压力区间C_(q)的回归模型,在不同压力区间以C_(q)最小为优化目标进行流道参数优化。【结果】引起C_(q)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l_(1)、弯道半径r、汇流段长l_(2)对其的影响可忽略不计。α、b、n对C_(q)的影响存在交互作用,C_(q)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C_(q)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(R^(2))分别为0.9967、0.9971,与调整后的复相关系数(Adj R^(2))差值均小于0.2。优化得到高压区最优方案的C_(q)要小于低压区,2个压力区优化方案C_(q)预测值与实测值相对误差分别为2.8%、2.3%。【结论】用C_(q)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C_(q)优化的结果可靠。
【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(C_(q)).Using single factor and the response surface test method,we studied experimentally how design parameters of the helical hedge flow channel affect C_(q).We then established and verified a regression model to calculate the variation of C_(q) with operating and design parameters,from which we proposed how to optimize the flow channel parameters with minimizing C_(q) as the optimization objective.【Result】The design parameters that affect C_(q) most are flow channel width b,the shunt angleαand number of flow channel units n.In contrast,the effect of straight section length l_(1),the bend radius r and the convergence section length l_(2) is negligible.The effect ofα,b and n on C_(q) is confounding.With the increase inα,b and n,C_(q) decreases first and then increases once it reaches the minimal value.C_(q) varies withα,b quadratically when the operating water pressure was low or high,with their associated correlation coefficient(R^(2))being 0.9967 and 0.9971 respectively.The difference between the adjusted correlation coefficients is less than 0.2.The C_(q) 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 C_(q) for the two pressure zones are 2.8%and 2.3%,respectively.【Conclusion】The regression model for variation of C_(q) with operating and design parameters is reliable,and the spiral hedge flow channel works better under high water pressure than under low water pressure.
作者
张军
李琳
ZHANG Jun;LI Lin(College of Hydraulic and Civil Engineering,Xinjiang Agricultural University,Urumqi 830052,China;Xinjiang Institute of Technology,Aksu 843000,China;Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention,Urumqi 830052,China)
出处
《灌溉排水学报》
CSCD
北大核心
2022年第7期57-64,共8页
Journal of Irrigation and Drainage
基金
新疆农业大学研究生“水利工程”重点学科研究项目(SLXK-YJS-2019-03)。
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
root emitter for fruit trees
spiral hedge flow channel
geometrical parameter
hydraulic performance
response surface method
