摘要
微喷带喷孔直径小,难以精准测量与加工,其单孔水力性能是微喷带标准化设计的瓶颈问题。为了精确预测微喷带喷孔水力特性,以内径32 mm无缝钢管为载体,采用精密激光技术加工了0.3、0.4、0.5、0.6和0.7mm 5种标准孔径喷孔,分别进行了10个压力水平下的流量测试,通过3次样条插值和多项式拟合构建了孔径-压力-流量模型,并与某进口微喷带0.3、0.35和0.54 mm 3种孔径的流量实测值进行了比较分析。研究结果表明,由实测数据建立的无缝钢管标准孔的压力流量公式拟合精度很高,决定系数均超过0.99;随着孔径的增大,小孔流量随压力变化较为敏感,且在较低压力下变化程度越加剧。由3次样条插值得到的孔径-压力-流量模型的预测精度总体上优于多项式拟合,前者预测的微喷带喷孔流量与实测值的相对误差绝对值是0.46%~4.69%,而后者达到0.91%~5.35%,而且预测小孔径0.3、0.35 mm的精度要优于大孔径0.54 mm。得到的无缝钢管标准孔径下压力流量特性以及孔径-压力-流量插值预测模型为微喷带产品的优化设计提供技术支撑。
The orifice of micro-sprinkling hose is difficult to measure and manufacture accurately because of its small size,so the hydraulic performance of single orifice has become the bottleneck of standardized design of micro-sprinkling hose.In order to predict the hydraulic behavior of orifice on micro-sprinkling hose accurately,a seamless steel tube with 32 mm inner diameter was used as the research object in this paper,and five standard orifices of 0.3,0.4,0.5,0.6 and 0.7 mm were fabricated by precision laser drilling technology.The flow rate tests at 10 pressure levels were carried out,and the diameter-pressure-discharge model was established by cubic spline interpolation and polynomial fitting respectively,whose results were compared with the measured flow rates of 0.3,0.35 and 0.54 mm orifices selected from an import micro-sprinkling hose.The results showed that the goodness of fit for the pressure flow formulas was very high based on the measured data of standard orifices of seamless steel tubes,whose determination coefficients were all more than 0.99.With the increase of orifice size,the flow rate of orifice was sensitive to the change of pressure,and the change degree was more severe at the lower pressure.The prediction accuracy of diameter-pressure-flow model obtained by cubic spline interpolation was generally better than that of polynomial fitting.The absolute relative error between the predicted flow rate and the measured value of the former was 0.46%~4.69%,while the latter reached 0.91%~5.35%,and the prediction accuracy of small sizes of 0.3 and 0.35 mm was better than that of large size of 0.54 mm.The pressure flow characteristics based on the orifices with standard size of seamless steel tube and the diameter-pressure-discharge interpolation prediction model obtained in this paper will provide technical support for the optimal design of micro-sprinkling hose products.
作者
霍倩
檀海斌
郑成海
HUO Qian;TAN Hai-bin;ZHENG Cheng-hai(School of Civil Engineering,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;Hebei Science and Technology Innovation Service Center,Shijiazhuang 050051,China)
出处
《节水灌溉》
北大核心
2023年第4期82-86,95,共6页
Water Saving Irrigation
基金
河北省重点研发计划项目(20327003D)。
关键词
微喷带
激光打孔
喷孔
水力性能
流量预测模型
micro-sprinkling hose
laser drilling
orifice
hydraulic performance
flow prediction model
