Newlysimplified method for hydraulic design of microirrigation laterals based on emission uniformity
Ju Xueliang1,2, Wu Pute1,2, Paul R. Weckler3, Zhu Delan2,4, Zhang Lin1,2
1.Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; 2.Institute of Water Saving Agriculture in Arid Areas of China, Northwest A&F University, Yangling, Shaanxi 712100, China; 3.Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, 74078, USA; 4.College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China)
Newlysimplified method for hydraulic design of microirrigation laterals based on emission uniformity
Ju Xueliang1,2, Wu Pute1,2, Paul R. Weckler3, Zhu Delan2,4, Zhang Lin1,2
1.Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China; 2.Institute of Water Saving Agriculture in Arid Areas of China, Northwest A&F University, Yangling, Shaanxi 712100, China; 3.Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, 74078, USA; 4.College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling, Shaanxi 712100, China)
摘要 An analytical approach was developed to design a single uniformly sloping lateral in the microirrigation systems. Emission uniformity was used as the water application uniformity criterion. Energy relations based on the energygradientline approach were revamped to account for the spatial variance of emitter outflow and the emitter connections local energy losses. Four pressure head grade line profiles were distinguished: uphill, horizontal, gentle downhill and steep downhill. Analytical expressions of emission uniformity by hydraulic variation for each pressure profile were developed based on the design variables: length and diameter of lateral, emitter spacing, emitter flow equation parameters, equivalent length characterizing local losses and ground slope. The design conditions for selecting emitter type, the number of emitters per plant and designing the diameter of the uphill and steep downhill laterals were also developed. The nonlinear equations for determining lateral diameter and lateral length were solved iteratively by using the builtin rootfinding function of (Tools> Goal Seek…) in the calculation spreadsheet of Microsoft Excel. The procedures also provide the options to fix the design lateral diameter with the commercial standard size or fix the design lateral length based on the field size. The operating inlet pressure and maximum amplitude of the pressure head throughout the lateral could also be determined easily by the procedure. Two numerical applications with various slope combinations indicate that the proposed analytical approach produces results close to the accurate stepwise numerical solutions. In comparison with Keller method, the proposed approach could produce more appropriate designs.
通讯作者:
Ju Xueliang (1987—), male, Ph.D candidate (juxueliang1987@nwsuaf.edu.cn), research fields: watersaving irrigation theory and technology.
作者简介: Wu Pute (1963—), male, professor (gjzwpt@vip.sina.com), research fields: high efficient utilization of water resources.
引用本文:
Ju Xueliang,, Wu Pute,, Paul R. Weckler, Zhu Delan,, Zhang Lin,. Newlysimplified method for hydraulic design of microirrigation laterals based on emission uniformity[J]. 排灌机械工程学报, 2015, 33(8): 691-700.
Ju Xueliang,, Wu Pute,, Paul R. Weckler, Zhu Delan,, Zhang Lin,. Newlysimplified method for hydraulic design of microirrigation laterals based on emission uniformity. Journal of Drainage and Irrigation Machinery Engin, 2015, 33(8): 691-700.
[1]Bralts V F, Driscoll M A, Shayya W H, et al. An expert system for the hydraulic analysis of microirrigation systems[J]. Computers and Electronics in Agriculture, 1993, 9(4): 275-287.[2]Warrick A W, Yitayew M. Trickle lateral hydraulics, I: Analytical solution[J]. Journal of Irrigation and Drainage Engineering, 1988, 114(2): 281-288.[3]Gillespie V A, Phillips A L, Wu I P. Drip irrigation design equation[J]. Journal of Irrigation and Drainage Engineering,1979, 105(3): 247-257.[4]Zayani K, Alouini A, Lebdi F, et al. Design of drip line in irrigation systems using the energy drop ratio approach[J]. Transaction of the ASAE, 2001, 44(5): 1051-1057.[5]Zayani K, Alouini A, Souissi A. Design of drip irrigation laterals using energy drop ratio approach[J]. Transactions of the ASAE, 2008, 51(6): 2029-2037.[6]Zayani K, Hammami M, Alouini A, et al. Design of nonzero uniformly sloping laterals in trickle irrigation systems[J]. Journal of Irrigation and Drainage Engineering, 2013, 139(5): 419-425.[7]Yildirim G. Simplified procedure for hydraulic design of smalldiameter plastic pipes[J]. Irrigation and Drainage, 2009, 58(2): 209-233.[8]Valiantzas J. Analytical approach for direct drip lateral hydraulic calculation[J]. Journal of Irrigation and Drainage Engineering, 1998, 124(6): 300-305.[9]Yildirim G. Hydraulic analysis and direct design of multiple outlets pipelines laid on flat and sloping lands[J]. Journal of Irrigation and Drainage Engineering, 2006, 132(6): 537-552.[10]Ravikumar V, Ranganathan C, Bosu S. Analytical equation for variation of discharge in drip irrigation laterals[J]. Journal of Irrigation and Drainage Engineering, 2003, 129(4): 295-298.[11]Keller J, Karmeli D. Trickle irrigation design parameters[J]. Transactions of the ASAE, 1974, 17(4): 678-684.[12]Keller J, Bliesner R D. Sprinkler and Trickle Irrigation[M]. New York: Van Nostrand Reinhold, 1990.[13]Juana L, Losada A, Rodrigoez-Sinobas L, et al. Analytical relationships for designing rectangular drip irrigation units[J]. Journal of Irrigation and Drainage Engineering, 2004, 130(1): 47-59.[14]Hathoot H M, Al-Amoud A I, Mohammad F S. Analysis and design of trickle irrigation laterals[J]. Journal of Irrigation and Drainage Engineering, 1993, 119(5): 756-767.[15]Kang Y H, Nishiyama S. Analysis and design of microirrigation laterals[J]. Journal of Irrigation and Drainage Engineering, 1996, 122(2): 75-81.[16]Hathoot H M, Al-Amoud A I, Al-Mesned A S. Design of trickle irrigation laterals considering emitter losses[J]. Irrigation and Drainage, 2000, 49(2): 1-14.[17]Scaloppi E J, Allen R G. Hydraulics of irrigation laterals: Comparative analysis[J]. Journal of Irrigation and Drainage Engineering, 1993, 119(1): 91-115.[18]Scaloppi E J. Adjusted F factor for multipleoutlet pipes[J]. Journal of Irrigation and Drainage Engineering, 1988, 114(1): 169-174.[19]Von Bernuth R. Simple and accurate friction loss equation for plastic pipe[J]. Journal of Irrigation and Drainage Engineering, 1990, 116(2): 294-298.[20]Yildirim G. Total energy loss assessment for trickle lateral lines equipped with integrated inline and online emitters[J]. Irrigation Science, 2010, 28(4): 341-352.[21]ASAE Subsurface and Trickle Irrigation Committee.ASABE Standard-EP4051 APR1988 (R2010), Design and Installation of Microirrigation Systems[S]. St. Joseph, Mich.: ASAE,2010.[22]Barragan J, Bralts V F, Wu I P. Assessment of emission uniformity for microirrigation design[J]. Biosystems Engineering, 2006, 93(1): 89-97.[23]Juana L, Rodriguez-Sinobas L, Losada A. Determining minor head losses in drip irrigation laterals. I: Methodology[J]. Journal of Irrigation and Drainage Engineering, 2002, 128(6): 376-384.[24]Juana L, Rodriguez-Sinobas L, Losada A. Determining minor head losses in drip irrigation laterals. Ⅱ: Experimental study and validation[J]. Journal of Irrigation and Drainage Engineering, 2002, 128(6): 385-396.