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Assessing sprinkler Irrigation Performance Using Field Evaluations at the Medjerda Lower Valley of Tunisia

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Engineering（科研） 2012年第10期4卷 682-691页

作者： Samir Yacoubi Khemaies Zayani Adel Slatni Enrique Playán Department Soil and Water Estación Experimental de Aula Dei CSIC. Zaragoza Spain High Institute of Environmental Science and Technology BP 1003 Hammam Lif 2050 Tunisia University of Carthage INRGREF BP 10 Ariana 2080 Tunisia University of Carthage

Irrigation uniformity and wind drift and evaporation losses (WDEL) are major concerns for the design and management of sprinkler irrigation systems under arid or semi-arid conditions. Field trials were carried out to assess irrigation uniformity and WDEL under various wind velocities, sprinkler spacings and operating pressure heads. Based on experimental data, a frequency analysis was performed to infer the occurrence probability of a given uniformity coefficient (UC). In addition, statistical regressions were used to model WDEL as a function of different climatic variables. Increasing the operating pressure head improved uniformity at low wind speeds. It was shown that UC has been severely impaired at wind speeds above 4 m/s. In the prevailing wind conditions, the frequency analysis showed that a sprinkler spacing of 12 m × 12 m provided the best uniformity. In the local conditions, it is recommended to stop irrigation when wind velocity exceeds 4 m/s. Moreover, it was shown that wind speed and relative humidity were the main significant variables influencing WDEL.

关键词： sprinkler Irrigation Uniformity Wind Drift and Evaporation Losses Wind Speed Pressure Head

Assessment cultivated period and farm yard manure addition on some soil properties, nutrient content and wheat yield under sprinkler irrigation system

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Agricultural Sciences 2013年第1期4卷 14-22页

作者： Ebtisam Eldardiry Farid Hellal Hani Mansour Mohamed Abd El Hady Plant Nutrition Department National Research Centre Giza Egypt Water Relations and Field Irrigation Department National Research Centre Giza Egypt

This study examined changes in some soil hydrophysical, chemical properties and wheat yield (grain;straw yield, N, P, K, Protein and carbohydrates contents) as trends under two cultivated period 10 and 25 year and Farm Yard manure (FYM) addition under sprinkler irrigation system on a newly reclaimed soils, Nubaria, Beheira Governorate, Egypt. Obtained results noticed that cultivation period has more pronounced effect than FYM addition on soil water content at field capacity, wilting point and available water with increase percent 15.1%, 9.3%;19.0% and 25.7%, 19.5% and 30.0% for FYM and cultivation period comparing with control one. Hydraulic conductivity values were strongly affected by cultivation period and FYM addition and significantly decreased values by about 18.9% and 12.1% in same sequences. Wheat straw content from protein had a superior effect under 25 than 10 years cultivated periods with values 61.9 and 6.7 comparing with control, respectively as affected by FYM addition, while FYM alone improved protein content in straw by about 31.9% comparing with untreated one. Slightly increase in straw protein content was attained relative to the increase of cultivated period by about 7.8%. Nutrients content in grain is more than FYM, where the increase percentage were 5.2%, 13.5%;3.8% and 26.5, 21.3;22.6 comparing cultivated periods 25 with 10 years and FYM addition with control, respectively. FYM individually under two studied cultivated periods is more effective under 10 years (28.0%, 25.2%;15.1%) than the 2nd one (25.1%, 25.2%;15.1%) comparing with untreated FYM plots. While N, P and K content in wheat straw had unclear trend and the increase were 6.8, 23.23;56.5% and 62.9, 6.0;29.8 as a result of FYM addition under 10 and 25 years cultivated periods, respectively. The highest values of protein and carbohydrates content in wheat grains as affected by studied factors were 12.86% and 67.43%) were obtained under cultivated period 25 years after FYM addition. Culti

关键词： Sandy Soil Hydrophysical Chemical Properties Farm Yard Manure Nutrient Content Irrigation Wheat Yield sprinkler

Calculation and verification of formula for the range of sprinklers based on jet breakup length

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International Journal of Agricultural and Biological Engineering 2018年第4期11卷 49-57页

作者： Yue Jiang Hong Li Chao Chen Qingjiang Xiang Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang 212013China

Jet breakup length is an important parameter which reflects the length of sprinkler *** on the linear instability theory,the dispersion equation of cylindrical jet was established and the theoretical value of jet breakup length was *** jet breakup length and initial amplitude of surface wave were measured by applying the high-speed photography ***,the numerical simulation was conducted by combining Level Set-VOF method for describing the jet breakup length to verify the theoretical and experimental *** the jet velocity and working pressure range of discussion,the results of comparison showed that the theoretical analysis gave a reasonable explanation to the influence of jet velocity,nozzle diameter and nozzle cone angle on jet breakup *** the theoretical value of jet breakup length with the experimental and simulated values,the three results accorded one *** experimental jet breakup lengths were the lowest and the simulation values were the largest,and the relative error was less than 10%,especially the theoretical value was closer to the average *** choosing the theoretical calculation of jet breakup length,a semi-empirical and semi-theoretical formula of range for the rotating sprinkler was concluded by the curve fitting method and the fitting formula was *** results showed the high accuracy of the ranges determined by this formula and the average relative error was less than 2.5%.The new formula was in good agreement with the data of different types of sprinklers comparing with other empirical formulas,and the error was only 5%.Meanwhile,the possibility of using this formula widely to determine the ranges of same series of sprinkler was confirmed.

关键词： sprinkler irrigation formula cylindrical jet jet breakup length dispersion equation high speed photography Level Set-VOF method

Irrigation and Thermal Buffering Using Mathematical Modeling

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Journal of Environmental & Earth Sciences 2024年第1期6卷 19-32页

作者： Yara Yasser Elborolosy Harsho Sanyal Joseph Cataldo The Albert Nerken School of Engineering at the Cooper Union New YorkNY 10003US

Two methods of irrigation,drip,and sprinkler were studied to determine the response of the Javits green roof to *** control study was dry unirrigated *** irrigation consisted of irrigation tubes running through the green roof that would water the soil throughout and sprinkler irrigation used a sprinkler system to irrigate the green roof from *** all cases,the irrigated roofs had increased the soil moisture,reduced temperatures of both the upper and lower surfaces,reduced growing medium temperatures and reduced air temperatures above the green roof relative to the unirrigated *** buffered temperature fluctuations were also studied via air conditioner energy *** was a 28%reduction in air conditioner energy consumption and a 33%reduction in overall energy consumption between dry and irrigated *** of thermal resistance or S were determined for accuracy and for this study,there was little change which is ideal.A series of infra-red and thermal probe measurements were used to determine temperatures in the air and *** was determined that the sprinkler irrigation did a better job than the drip irrigation in keeping cooler temperatures within the green roof.A Mann-Whitney U test was performed to verify the variation in moisture temperatures buffering energy *** getting a p-value<0.05,it indicates that the model is accurate for prediction and medium temperatures were statistically different.

关键词： Green roofs Irrigation Drip sprinkler Thermal buffering

Temperature and Humidity Control in Greenhouses in Desert Areas

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Agricultural Sciences 2014年第13期5卷 1261-1268页

作者： Shigeki Hirasawa Mai Nakatsuka Kunio Masui Tsuyoshi Kawanami Katsuaki Shirai Department of Mechanical Engineering Kobe University Kobe Japan

Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and humidity in a greenhouse under various desert area conditions. We calculated the changes in temperature and humidity in a greenhouse for a whole day in four seasons, and the calculation results of water consumption with and without a greenhouse were compared. When ventilation, shielding, and sprinkler water were controlled under suitable conditions to grow orchids in a desert area, water consumption in July was only 7% of that without a greenhouse.

关键词： Temperature Control Humidity Ventilation sprinkler Water Heat Transfer Greenhouse Desert

Effects of Water Distribution Uniformity on Waxy Corn (<i>Zea mays</i>L.) Yield: Preliminary Results

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Journal of Water Resource and Protection 2014年第11期6卷 1037-1044页

作者： Lucia Bortolini Marco Martello Department of Land Environment Agriculture and Forestry (TESAF) University of Padova Padova Italy

To face climatic changes, the increase of frequency and severity of droughts, and economic development pressures, Water Management Institutions point at the necessity of water conserving. A sustainable demand-led approach is the most viable option, focusing on achieving more efficient irrigation practices instead of less sustainable expansion of supply. The aim of this work is to investigate on some aspects of the rational water management for the irrigation of corn in order to evaluate the actual possibility of introduction of drip irrigation systems on the Venetian Plain. Trials were carried out on a farm located in Isola della Scala (Verona, Italy) in an area of about 13 ha (12 ha with a drip irrigation system and 1 ha with a solid-set sprinkler system);the effects of the performance of the two systems on waxy corn yield were considered. In particular, water distribution uniformity, water use efficiency, and yield performance of irrigation systems were evaluated. DUlq and CU coefficients for distribution uniformity and IWUe and WUEb indexes for water use efficiency were calculated. To visualize and better analyze the distribution uniformity, the crop yield and the efficiency parameters, ArcGIS 10 (ESRI?) with IDW interpolation were used to create maps. First results show a good water uniformity distribution in the drip irrigation system but only with a careful and proper design of the entire system. As regards the water use efficiency, drip irrigation values are lower than those of sprinkler irrigation (-46% for IWUe and -25% for WUEb), probably due to different irrigation management and water volumes used: in fact, drip irrigation was scheduled every three days, while only supplemental operations were done for sprinkler irrigation. No statistical correlation was found between application rate and yield for both irrigations systems, while a significant correlation was found between irrigation volume and crop water use efficiency. The profitability of the two irri

关键词： Drip Irrigation sprinkler Irrigation Profitability Efficiency GIS

Root-Zone Soil Water Balance and Sunflower Yield under Deficit Irrigated in Zambia

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Open Journal of Soil Science 2018年第1期8卷 61-73页

作者： Elijah Phiri Simon Zimba Department of Soil Science School of Agricultural Sciences University of Zambia Lusaka Zambia Natural Resources Development College Lusaka Zambia

The study was conducted at the University of Zambia, Research Field Station, Lusaka, Zambia to evaluate the root zone soil water balance under full, and deficit irrigated sunflower. The specific objectives were: 1) to assess the sunflower growth and yield under varying irrigation water regimes;2) to evaluate the root-zone water balance;and 3) to evaluate the water use efficiency of sunflower. Sunflower (Helianthus annuus, var Milika) was planted in a Randomized Complete Block Design (RCBD) with four irrigated water regimes in four replications. The treatments comprised: treatment (T1) = 30% ETc;treatment (T2) = 54% ETc;treatment (T3) = 65% ETc;and treatment (T4) = 100% ETc. The sunflower crop was irrigated on a weekly irrigation schedule using sprinklers. The measured parameters included: weather data, soil moisture profiles, growth stages (emergence, flowering, maturity), above-ground biomass, and grain yield. The results of the study showed that growth parameter (biomass and seed yield) decreased with a decrease in applied irrigation water. The sunflower seed yield varied from 0.22 to 1.40-ton·ha-1 with an average yield of 0.81-ton·ha-1. The highest grain yield was obtained under treatment (T4), and the least grain in yield harvest was at treatment (T1). The statistical analysis showed significant differences in seed yield among the treatments. The treatments (T1 and T2) were not significantly different (p > 0.05). These results showed that when water deficit was set at 65% and 100% ETc and uniformly distributed throughout the sunflower growth, there were no significant differences in biomass, stover and seed yield. In literature, the allowable soil moisture depletion factor for irrigation scheduling of sunflower is set at 45%. The yield components decreased as irrigation levels decreased for each irrigation interval. The 65% ETc treatment could be recommended for sunflower irrigated in semi-arid regions and be used as a good basis for improved irrigation strategy

关键词： Crop Water Requirements Water Use Efficiency sprinkler Irrigation Water Productivity

Energy Analysis in Irrigated Sugarcane Schemes of Awash River Basin, Ethiopia

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Computational Water, Energy, and Environmental Engineering 2022年第4期11卷 93-115页

作者： Yusuf Kedir Belete Berhanu Tena Alamirew Addis Ababa Institute of Technology (AAiT) Addis Ababa Ethiopia Civil and Environmental Engineering Department Addis Ababa Institute of Technology (AAiT) Addis Ababa Ethiopia Ethiopian Institute of Water Resources Addis Ababa Ethiopia

Sugarcane is one of the important irrigated crops in Ethiopia and its production is highly linked with its energy and water use. In this paper, identifications and quantifications of input and output, direct and indirect energy sources, and energy use of farm operations were carried out on 11 irrigation schemes of Awash River Basin. In order to grow 91.8 to 167.6 tons of cane, 47.9 to 143.4 GJ/ha of total energy was used. Average total input energies of gravity, pump surface and sprinkler scheme categories to grow 109.8, 112.7 and 136.3 ton/ha were 53.6, 68.9 and 129.2 GJ/ha, respectively. Around 90% and 74% total energies of gravity surface and sprinkler schemes were consumed as direct and indirect energies, respectively. Irrigation found to be the most energy consuming operation constituting more than 50% input energy of all scheme categories. Energy efficiency of gravity schemes was 152% and 300% higher than pump driven surface and sprinkler schemes. Energy sequestrated in cane straws burned during harvesting found to be higher than fertilizer and pumping energy demands. Use of cane straws as manure and energy sources have the potential to substitute demands which in turn needs further investigations and analysis.

关键词： Energy Productivity Energy Sources Farm Operation Gravity Scheme Pump Scheme sprinkler