对冲喷头设计与雾化试验
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摘要
【目的】针对植保机械扇形喷头雾滴粒谱较宽、雾滴粒径均匀度较差等不足,基于射流和撞击流耦合作用原理,提出一种新型喷头结构方案,以改善喷头雾滴粒径均匀性和雾滴谱。【方法】采用快速成型制造技术的光敏液相固化成型(SLA)工艺,选用C-UV9400立体光造型树脂材料,制造出喷头终端喷孔出水口形状相同、出水口孔径d_1=1 mm、切槽角α=30°的扇形喷头和新型对冲喷头;利用喷头雾化性能测试系统检测2种喷头的雾滴粒径和雾滴分布情况,使用分布跨度评价雾滴粒径均匀性。【结果】在距喷头终端喷孔出水口100 mm处,喷施压力在0.3～0.8 MPa范围内变化时,扇形喷头和新型对冲喷头的分布跨度分别在1.65～1.82和1.07～1.23之间,分布跨度小表明雾滴粒径均匀性好、雾滴谱窄,且从测得的雾滴分布图发现,新型对冲喷头的雾滴分布较集中;当喷施压力大于0.6 MPa时,扇形喷头雾滴粒径变化趋向稳定,而新型对冲喷头雾滴粒径随喷施压力增大还能不断减小,表明新型对冲喷头具有调压范围宽的良好调压特性;撞击后会形成较大雾滴,较大雾滴并有一定速度具备较好的穿透性能和抗飘移能力;为使喷头达到较佳的病虫害防治效果,建立了喷头雾滴粒径多项式回归模型,为喷头选用提供依据。【结论】基于射流和撞击流耦合作用的对冲喷头具有雾滴粒径均匀性较好、雾滴谱较窄、调压范围宽和抗飘性较强的特点,可为开发精准施药植保机械装备提供技术支持。
【Objective】 In view of the deficiencies that spray droplets were wider in flat-fan nozzle of plant protection machinery, and particle size uniformity were insufficient, a new type of nozzle structure based on the coupling of jet and impinging jets was proposed to improve the spray droplet size uniformity and the droplet spectrum.【Method】 Using photosensitive liquid phase curing molding process of rapid prototyping manufacturing technology and C-UV9400 stereoscopic light modeling resin material, the flat-fan nozzle and impinging nozzle were produced which had the same exit shape, exit diameter(d_1=1 mm)and groove angle(α=30°). The droplet size and droplet distribution of the two kinds of nozzles were obtained according to the test system for atomizing performance of nozzle, and the uniformity of the particle size was evaluated in terms of the international criteria for distribution span.【Result】 At the position 100 mm away from the nozzle exit, when the spraying pressure changed within the range of 0.3-0.8 MPa, it was found that the S value of the distribution span of flat-fan nozzle and impinging nozzle were respectively between 1.65-1.82 and 1.07-1.23, in which the smaller S value stands for better uniform and narrower spectrum, and the spraying performance test system showed that the droplet were more concentrated; the droplet size of flat-fan nozzle tended to be stable when the spraying pressure was greater than 0.6 MPa, and the droplet size of impinging nozzle decreased with the increase of spraying pressure, which indicated that the impinging nozzle had a variable pressure regulating performance with wide pressure regulating range; large droplets will be formed after impact, and larger droplets with a certain speed had better penetration performance and anti-drift ability. Besides, a multiple regression model of droplet size was established to provide a basis for selecting nozzle to achieve a better pest control.【Conclusion】 The impinging nozzle based on the coupling of jet and impinging jets had the characteristics of improving particle size uniformity, narrow droplet spectrum, wide range of pressure regulation and better anti-drift ability. It can provide technical support for developing precision sprayer.
【Objective】 In view of the deficiencies that spray droplets were wider in flat-fan nozzle of plant protection machinery, and particle size uniformity were insufficient, a new type of nozzle structure based on the coupling of jet and impinging jets was proposed to improve the spray droplet size uniformity and the droplet spectrum.【Method】 Using photosensitive liquid phase curing molding process of rapid prototyping manufacturing technology and C-UV9400 stereoscopic light modeling resin material, the flat-fan nozzle and impinging nozzle were produced which had the same exit shape, exit diameter(d_1=1 mm)and groove angle(α=30°). The droplet size and droplet distribution of the two kinds of nozzles were obtained according to the test system for atomizing performance of nozzle, and the uniformity of the particle size was evaluated in terms of the international criteria for distribution span.【Result】 At the position 100 mm away from the nozzle exit, when the spraying pressure changed within the range of 0.3-0.8 MPa, it was found that the S value of the distribution span of flat-fan nozzle and impinging nozzle were respectively between 1.65-1.82 and 1.07-1.23, in which the smaller S value stands for better uniform and narrower spectrum, and the spraying performance test system showed that the droplet were more concentrated; the droplet size of flat-fan nozzle tended to be stable when the spraying pressure was greater than 0.6 MPa, and the droplet size of impinging nozzle decreased with the increase of spraying pressure, which indicated that the impinging nozzle had a variable pressure regulating performance with wide pressure regulating range; large droplets will be formed after impact, and larger droplets with a certain speed had better penetration performance and anti-drift ability. Besides, a multiple regression model of droplet size was established to provide a basis for selecting nozzle to achieve a better pest control.【Conclusion】 The impinging nozzle based on the coupling of jet and impinging jets had the characteristics of improving particle size uniformity, narrow droplet spectrum, wide range of pressure regulation and better anti-drift ability. It can provide technical support for developing precision sprayer.
引文
邓巍, 孟志军, 陈立平, 等. 2011. 农药喷雾液滴尺寸和速度测量方法. 农机化研究,(5): 26-30.(Deng W, Meng Z J, Chen L P, et al. 2011. Measurement methods of spray droplet size and velocity. Journal of Agricultural Mechanization Research, (5): 26-30. [in Chinese])
董福龙,周宏平. 2018. 国外植保喷头技术开发进展. 江西农业大学学报, 40(4): 866-874.(Dong F L, Zhou H P. 2018. Development of foreign nozzles. Journal of Jiangxi Agricultural University, 40(4): 866-874. [in Chinese])
董志勇. 2005. 射流力学. 北京: 科学出版社.(Dong Z Y. 2005. Jet mechanics. Beijing: Science Press. [in Chinese])
金颖磊,潘伟杰,吕健,等. 2017. 基于可拓语义分析的文化创意产品设计方法研究. 工程设计学报, 24(1): 27-33.(Jin Y L, Pan W J, Lü J, et al. 2017. Study on cultural and creative product design method based on extension semantics analysis. Chinese Journal of Engineering Design, 24(1): 27-33. [in Chinese])
李秉礼. 1984. 植保机械. 北京: 科学普及出版社.(Li B L. 1984. Plant protection machinery. Beijing: Science Popularization Press. [in Chinese])
李旭, 吴春笃, 王光亮, 等. 2002. 低流量扇形雾喷头的设计. 农业机械学报,33(4): 38-41.(Li X, Wu C D, Wang G L, et al. 2002. Design of a low atomizer with fan-shaped spraying. Journal of Agricultural Machinery, 33(4): 38-41. [in Chinese])
吕晓兰,何雄奎,宋坚利,等. 2007. 标准扇形喷头雾化过程测试分析. 农业工程学报,23(9): 95-100.(Lü X L, He X K, Song J L, et al. 2007. Analysis of spray process produced by agriculture flat-fan nozzles. Transactions of the Chinese Society of Agricultural Engineering, 23(9): 95-100. [in Chinese])
齐晓霓. 2008. 无填料冷却塔的理论与实验研究. 上海: 上海交通大学博士学位论文.(Qi X N. 2008. Research on the shower cooling tower. Shanghai: PhD thesis of Shanghai Jiao Tong University. [in Chinese])
茹煜,金兰,周宏平,等. 2014. 航空施药旋转液力雾化喷头性能试验. 农业工程学报, 30(3): 50-55.(Ru Y, Jin L, Zhou H P, et al. 2014. Performance experiment of rotary hydraulic atomizing nozzle for aerial spraying application. Transactions of the Chinese Society of Agricultural Engineering, 30(3): 50-55. [in Chinese])
时玲,张霞,吴红生,等. 2011. 扇形喷头雾量分布均匀性的试验研究. 云南农业大学学报,26(3): 389-394.(Shi L, Zhang X, Wu H S, et al. 2011. Experimental research on spray distribution uniformity of fan nozzle. Journal of Yunnan Agricultural University, 26(3): 389-394. [in Chinese])
谢晨,何雄奎,宋坚利,等. 2013. 两类扇形雾喷头雾化过程比较研究. 农业工程学报,29(5): 25-30.(Xie C, He X K, Song J L, et al. 2013. Comparative research of two kinds of flat fan nozzle atomization process. Transactions of the Chinese Society of Agricultural Engineering, 29(5): 25-30. [in Chinese])
王永生, 陈静, 陶欢, 等. 2016. 精准农业技术对生态环境的影响评价研究进展. 中国农业科技导报,18(4): 73-78.(Wang Y S, Chen J, Tao H, et al. 2016. Research progress on impact evaluation of precision agriculture technology on ecological environment. Journal of Agricultural Science and Technology, 18(4): 73-78. [in Chinese])
伍沅. 2006. 撞击流—原理·性质·应用. 北京: 化学工业出版社.(Wu Y. 2006. Impinging jets, principle,properties, applications. Beijing: Chemical Industry Press. [in Chinese])
翟恩昱. 2012. 扇形雾喷头磨损规律和失效预测研究. 南京: 南京林业大学博士学位论文.(Zhai E Y. Study on wear characteristics and failure prediction of flat-fan nozzles. Nanjing: PhD thesis of Nanjing Forestry University.[in Chinese])
张辉, 张永江, 杨易. 2018. 美国、加拿大精准农业发展实践及启示. 世界农业,(1): 175-178.(Zhang H, Zhang Y J, Yang Y. 2018. Practice and Enlightenment of precision agriculture development in USA and Canada. World Agriculture, (1): 175-178. [in Chinese])
张慧春,Dorr Gary,郑加强,等. 2012. 扇形喷头雾滴粒径分布风洞试验. 农业机械学报,43(6): 52-57.(Zhang H C, Dorr G, Zheng J Q, et al. 2012. Wind tunnel experiment of influence on droplet size distribution of flat nozzles. Journal of Agricultural Machinery,43(6): 52-57. [in Chinese])
Andsaler A R, Khalid A, Abdullah N S A, et al. 2017. The effect of orifice diameter in constant volume chamber to spray characteristics in diesel engine using computational fluid dynamic. The 2nd International Conference on Automotive Innovation and Green Vehicle, 1-12.
Ashgriz N, Givi P. 1987. Binary collision dynamics of fuel droplets. International Journal of Heat & Fluid Flow, 8(3): 205-210.
Huang L X, Kumar K, Mujumdar A. 2006. A comparative study of a spray dryer with rotary disc atomizer and pressure nozzle using computational fluid dynamic simulations. Chemical Engineering and Processing, 45(6): 461-470.
Miller P C H, Ellis M C B, Tuck C R. 1996. Entrained air and droplet velocities produced by agricultural flat-fan nozzle. Atomization and Sprays, 6(6): 693-707.
Nuyttens D, Baetens K, Schampheleire M D, et al. 2007. Effect of nozzle type, size and pressure on spray droplet characteristics. Biosystems Engineering, 97(3): 333-345.
Robert N K, Jeffrey A G. 2004. The effect of spray particle size and distribution on drift and efficacy of herbicides. Aspects of Applied Biology 71, International Advances in Pesticide Application, 71: 44-51.
Sande E V D, Smith J M. 1973. Surface entrainment of air by high velocity water jets. Chemical Engineering Science, 28(5): 1161-1168.
Tuck C R, Ellis M C B, Miller P C H. 1997. Techniques for measurement of droplet size and velocity distributions in agricultural sprays. Crop Protection, 16(7): 619-628.
董福龙,周宏平. 2018. 国外植保喷头技术开发进展. 江西农业大学学报, 40(4): 866-874.(Dong F L, Zhou H P. 2018. Development of foreign nozzles. Journal of Jiangxi Agricultural University, 40(4): 866-874. [in Chinese])
董志勇. 2005. 射流力学. 北京: 科学出版社.(Dong Z Y. 2005. Jet mechanics. Beijing: Science Press. [in Chinese])
金颖磊,潘伟杰,吕健,等. 2017. 基于可拓语义分析的文化创意产品设计方法研究. 工程设计学报, 24(1): 27-33.(Jin Y L, Pan W J, Lü J, et al. 2017. Study on cultural and creative product design method based on extension semantics analysis. Chinese Journal of Engineering Design, 24(1): 27-33. [in Chinese])
李秉礼. 1984. 植保机械. 北京: 科学普及出版社.(Li B L. 1984. Plant protection machinery. Beijing: Science Popularization Press. [in Chinese])
李旭, 吴春笃, 王光亮, 等. 2002. 低流量扇形雾喷头的设计. 农业机械学报,33(4): 38-41.(Li X, Wu C D, Wang G L, et al. 2002. Design of a low atomizer with fan-shaped spraying. Journal of Agricultural Machinery, 33(4): 38-41. [in Chinese])
吕晓兰,何雄奎,宋坚利,等. 2007. 标准扇形喷头雾化过程测试分析. 农业工程学报,23(9): 95-100.(Lü X L, He X K, Song J L, et al. 2007. Analysis of spray process produced by agriculture flat-fan nozzles. Transactions of the Chinese Society of Agricultural Engineering, 23(9): 95-100. [in Chinese])
齐晓霓. 2008. 无填料冷却塔的理论与实验研究. 上海: 上海交通大学博士学位论文.(Qi X N. 2008. Research on the shower cooling tower. Shanghai: PhD thesis of Shanghai Jiao Tong University. [in Chinese])
茹煜,金兰,周宏平,等. 2014. 航空施药旋转液力雾化喷头性能试验. 农业工程学报, 30(3): 50-55.(Ru Y, Jin L, Zhou H P, et al. 2014. Performance experiment of rotary hydraulic atomizing nozzle for aerial spraying application. Transactions of the Chinese Society of Agricultural Engineering, 30(3): 50-55. [in Chinese])
时玲,张霞,吴红生,等. 2011. 扇形喷头雾量分布均匀性的试验研究. 云南农业大学学报,26(3): 389-394.(Shi L, Zhang X, Wu H S, et al. 2011. Experimental research on spray distribution uniformity of fan nozzle. Journal of Yunnan Agricultural University, 26(3): 389-394. [in Chinese])
谢晨,何雄奎,宋坚利,等. 2013. 两类扇形雾喷头雾化过程比较研究. 农业工程学报,29(5): 25-30.(Xie C, He X K, Song J L, et al. 2013. Comparative research of two kinds of flat fan nozzle atomization process. Transactions of the Chinese Society of Agricultural Engineering, 29(5): 25-30. [in Chinese])
王永生, 陈静, 陶欢, 等. 2016. 精准农业技术对生态环境的影响评价研究进展. 中国农业科技导报,18(4): 73-78.(Wang Y S, Chen J, Tao H, et al. 2016. Research progress on impact evaluation of precision agriculture technology on ecological environment. Journal of Agricultural Science and Technology, 18(4): 73-78. [in Chinese])
伍沅. 2006. 撞击流—原理·性质·应用. 北京: 化学工业出版社.(Wu Y. 2006. Impinging jets, principle,properties, applications. Beijing: Chemical Industry Press. [in Chinese])
翟恩昱. 2012. 扇形雾喷头磨损规律和失效预测研究. 南京: 南京林业大学博士学位论文.(Zhai E Y. Study on wear characteristics and failure prediction of flat-fan nozzles. Nanjing: PhD thesis of Nanjing Forestry University.[in Chinese])
张辉, 张永江, 杨易. 2018. 美国、加拿大精准农业发展实践及启示. 世界农业,(1): 175-178.(Zhang H, Zhang Y J, Yang Y. 2018. Practice and Enlightenment of precision agriculture development in USA and Canada. World Agriculture, (1): 175-178. [in Chinese])
张慧春,Dorr Gary,郑加强,等. 2012. 扇形喷头雾滴粒径分布风洞试验. 农业机械学报,43(6): 52-57.(Zhang H C, Dorr G, Zheng J Q, et al. 2012. Wind tunnel experiment of influence on droplet size distribution of flat nozzles. Journal of Agricultural Machinery,43(6): 52-57. [in Chinese])
Andsaler A R, Khalid A, Abdullah N S A, et al. 2017. The effect of orifice diameter in constant volume chamber to spray characteristics in diesel engine using computational fluid dynamic. The 2nd International Conference on Automotive Innovation and Green Vehicle, 1-12.
Ashgriz N, Givi P. 1987. Binary collision dynamics of fuel droplets. International Journal of Heat & Fluid Flow, 8(3): 205-210.
Huang L X, Kumar K, Mujumdar A. 2006. A comparative study of a spray dryer with rotary disc atomizer and pressure nozzle using computational fluid dynamic simulations. Chemical Engineering and Processing, 45(6): 461-470.
Miller P C H, Ellis M C B, Tuck C R. 1996. Entrained air and droplet velocities produced by agricultural flat-fan nozzle. Atomization and Sprays, 6(6): 693-707.
Nuyttens D, Baetens K, Schampheleire M D, et al. 2007. Effect of nozzle type, size and pressure on spray droplet characteristics. Biosystems Engineering, 97(3): 333-345.
Robert N K, Jeffrey A G. 2004. The effect of spray particle size and distribution on drift and efficacy of herbicides. Aspects of Applied Biology 71, International Advances in Pesticide Application, 71: 44-51.
Sande E V D, Smith J M. 1973. Surface entrainment of air by high velocity water jets. Chemical Engineering Science, 28(5): 1161-1168.
Tuck C R, Ellis M C B, Miller P C H. 1997. Techniques for measurement of droplet size and velocity distributions in agricultural sprays. Crop Protection, 16(7): 619-628.