A New Irrigation System of Zero/Negative Pressure and the Experimental Verification of Its Feasibility
Jiang Peifu, Tingwu Lei, Juan Xiao, Yingduo Yu, Vincent F. Bralts · 2004, Ottawa, Canada August 1 - 4, 2004 · 2004
A new irrigation technology which works at zero or negative pressure was advanced, onthe basis of soil water dynamics. The system is designed to be operated under such conditions: theelevation of the emitters was are at the same (for zero pressure) or higher elevation (for negativepressure) the water source, with no pressurization necessary. The working principles or the physicbasis of the newly suggested technology was briefed in the paper. A series of laboratory experimentswere arranged to verify the feasibility of the method. Porous ceramic tubing were used in theexperiments as water application emitters, with 7 elevation differences between water source and theemitter(s) as: 0.5, 0, -0.5, -1.0, -2, -3 and -4 m. The experimental data were used to quantify therelationships between elevation differences and cumulative infiltration; the maximum wetteddistances in horizontal and vertical directions as well as the dynamic advances of wetting fronts. Theexperimental results were used to estimate the emitter number per unit area as related to crop waterrequirement. The results demonstrated the feasibility of the method. This newly suggestedzero/negative pressure irrigation system needs no equipment or power to pressurize the system,which can save cost and energy sources. The system as a water efficient irrigation should find itsapplications to many circumstances.