采用二次通用回归旋转组合设计方法,对KDP晶体的切削加工工艺进行优化设计;利用单点金刚石飞刀切削(single point diamond turning,SPDT)技术对其进行切削。对试验结果进行测量与分析,确定合理的试验因素及水平,分析加工工艺参数的单因...采用二次通用回归旋转组合设计方法,对KDP晶体的切削加工工艺进行优化设计;利用单点金刚石飞刀切削(single point diamond turning,SPDT)技术对其进行切削。对试验结果进行测量与分析,确定合理的试验因素及水平,分析加工工艺参数的单因素和交互因素对KDP晶体表面粗糙度的影响规律。最后得到最优工艺参数组合:刀具圆弧半径为5 mm,转速为800 r/min,进给量为1μm/r,背吃刀量为21μm,加工出的KDP晶体表面粗糙度值为0.017μm。展开更多
The purpose of this study was to promote the development of large-scale agricultural machines in China and meet the demand of air seeder localization.This study investigated the relationship between the working parame...The purpose of this study was to promote the development of large-scale agricultural machines in China and meet the demand of air seeder localization.This study investigated the relationship between the working parameters and the performance of pneumatic seeding system,Cangmai 6004 wheat seed was used.A test platform for pneumatic seeding systems was developed,and then a series of experiments were performed based on the quadratic general rotary unitized design and response surface methodology(RSM).The seeding rate and the air flow rate were selected as affecting factors,coefficient of variation(CV)of evenness of feeding rate between rows and CV of seeding stability of total rows were assigned as the test indexes.Regression models between factors and indexes were established,and finally,an optimal equation based on this pneumatic seeding system were established as well,which can determine the proper air flow rate once the seeding rate was set based on the practical agronomic requirements.For example,when the seeding rate is set as 250 kg/hm^(2),the proper air flow rate of 7.53 m3/min can be obtained.The verification experiment results showed that the predicted working parameters obtained by RSM were feasible,which might provide a theoretical basis for further research of pneumatic seed metering systems.展开更多
Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate spra...Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate sprayer parameters for kiwifruit trees,the vertical distribution profiles of the applied liquid spray were examined in this study.The effects of spray fan speed(SFS),spray pressure(SP)and spray distance(SD)on the distributions of the sprayed liquid in the vertical profiles were studied.Combined actions of the above parameters were systematically analysed using the quadratic general rotary design test method.Regression equations for the spray liquid distributions and working factors are presented.Field confirmation experiments were carried out to optimize the parameters.Data analysis showed that the optional sprayer working parameters are those of Group 3,with an SFS equal to 1900 r/min and SP equal to 3.25 MPa.The results of this study provide a reference for future applications of this type of axial air-assisted sprayer in kiwifruit orchards.展开更多
基金the Chinese Academy of Agricultural Mechanization Sciences,State Key Laboratory of Soil Plant Machinery System Technology,and the supports of the Rural Areas National Key Technology R&D Program during the Twelfth Five-year Plan Period-Development of Farm Work Equipment Matched on Large Horsepower Tractors(2011BAD20B03).
文摘The purpose of this study was to promote the development of large-scale agricultural machines in China and meet the demand of air seeder localization.This study investigated the relationship between the working parameters and the performance of pneumatic seeding system,Cangmai 6004 wheat seed was used.A test platform for pneumatic seeding systems was developed,and then a series of experiments were performed based on the quadratic general rotary unitized design and response surface methodology(RSM).The seeding rate and the air flow rate were selected as affecting factors,coefficient of variation(CV)of evenness of feeding rate between rows and CV of seeding stability of total rows were assigned as the test indexes.Regression models between factors and indexes were established,and finally,an optimal equation based on this pneumatic seeding system were established as well,which can determine the proper air flow rate once the seeding rate was set based on the practical agronomic requirements.For example,when the seeding rate is set as 250 kg/hm^(2),the proper air flow rate of 7.53 m3/min can be obtained.The verification experiment results showed that the predicted working parameters obtained by RSM were feasible,which might provide a theoretical basis for further research of pneumatic seed metering systems.
基金The authors acknowledge that this work was financially supported by the National Key Research and Development Program(No.2016YFD0200700)the National Key R&D Program of China“the 13th Five-Year Plan”(Grant No.2016YFD0700503)the Science and Technology Project of Shaanxi Province.Also,we thank the critical comments and suggestions from the anonymous reviewers for improving the manuscript.
文摘Axial air-assisted sprayers can distribute pesticides efficiently in kiwifruit orchards.Because of improper parameter settings,most sprayers deliver either too much or too little pesticide.To identify appropriate sprayer parameters for kiwifruit trees,the vertical distribution profiles of the applied liquid spray were examined in this study.The effects of spray fan speed(SFS),spray pressure(SP)and spray distance(SD)on the distributions of the sprayed liquid in the vertical profiles were studied.Combined actions of the above parameters were systematically analysed using the quadratic general rotary design test method.Regression equations for the spray liquid distributions and working factors are presented.Field confirmation experiments were carried out to optimize the parameters.Data analysis showed that the optional sprayer working parameters are those of Group 3,with an SFS equal to 1900 r/min and SP equal to 3.25 MPa.The results of this study provide a reference for future applications of this type of axial air-assisted sprayer in kiwifruit orchards.
