scholarly journals Effects of Travel Speed and Collector on Evaluation of the Water Application Uniformity of a Center Pivot Irrigation System

Water ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1916 ◽  
Author(s):  
Yongchong Li ◽  
Xin Hui ◽  
Haijun Yan ◽  
Diyi Chen
Keyword(s):  
Cross Section ◽  
Irrigation System ◽  
Weighted Average ◽  
Travel Speed ◽  
Application Rate ◽  
Water Application ◽  
Center Pivot ◽  
Average Water ◽  
Coefficient Of Uniformity ◽  
Selection Of

Water application uniformity is an important performance parameter when designing and operating an irrigation system. Performance tests of a center pivot irrigation system equipped with fixed and rotated spray plate sprinklers (FSPS and RSPS, respectively) were conducted at five travel speeds. The effects of travel speed, collector size, and setting height on water application uniformity were evaluated using Heermann and Hein’s coefficient of uniformity (CUH). The CUH was 12.7% higher for the RSPS than the FSPS and decreased as the travel speed increased. Collector size and setting height affected CUH, and CUH was higher when the collector had a large opening cross-section compared to the collector with a small opening cross-section. CUH was higher when the collector with a low setting height compared to when it a high setting height for the FSPS. However, collector setting height had no effect on CUH for the RSPS. The weighted average water application depth (Dw) decreased as the travel speed increased. Collector size had no significant effect on Dw, but Dw with a low collector setting height was larger than the values with a high collector setting height. The water application rate increased as distance from the pivot point increased and was higher for the FSPS than the RSPS. The results will improve the selection of travel speed and collector when the water application uniformity of a center pivot irrigation system is evaluated.

scholarly journals Water distribuition characteristics and soil loss of LEPA Quad-Spray emitter nozzles

2013 ◽  
Vol 33 (2) ◽  
pp. 223-236 ◽  
Author(s):  
Moises S. Ribeiro ◽  
Luiz A. Lima ◽  
Alberto Colombo ◽  
Ana C. D. M. Caldeira ◽  
Fabio H. de S. Faria
Keyword(s):  
Flow Rate ◽  
Soil Loss ◽  
Water Distribution ◽  
Weighted Average ◽  
Application Rate ◽  
Nozzle Diameter ◽  
Water Application ◽  
Application Rates ◽  
Average Water ◽  
Pattern Width

The objective of this study was to characterize water application rate, water application pattern width, flow rate, water distribution uniformity and soil loss caused by nozzles of the Low Energy Precision Aplication (LEPA) type Quad-Spray emitter. The study was carried out at the Hydraulic and Irrigation Laboratory of the Department of Engineering at the Federal University of Lavras, in Lavras, state of Minas Gerais - MG, Brazil. Twenty-two (22) LEPA Quad-Spray emitter nozzles were evaluated, with nozzle diameter ranging from 1.59 to 9.92 mm. The experimental design used was entirely randomized, with three replications.Increasing values of nozzle flow rate ranging from 77.44 up to 3,044 L h-1, were obtained with increasing nozzle diameter sizes. Application pattern width ranged from 0.56 up to 3.24m, according to nozzles diameter size. Low values of CDU (maximum of 35.73%) were observed when using the Quad-Spray nozzles. Observed average water application rates covered the range between 68.05 mm h-1 (the lowest value that was obtained with the 2.38mm nozzle) and 258.15 mm h-1 (the highest value that was observed with the 9.92 mm). Average water application rates increased in a simple non-linear function with the increase of nozzle size diameter. However, the weighted average increase in the amount of soil loss by erosion was not related to the increase of weighted average water application values.

scholarly journals PERFORMANCE EVALUATION OF HYDRAULIC PARAMETERS OF A DEVELOPED DRIP IRRIGATION SYSTEM

2019 ◽  
Vol 31 (2) ◽  
Author(s):  
Olorunwa Eric Omofunmi ◽  
Oluwaseun Ayodele Ilesanmi ◽  
Toluwalase Orisabinone
Keyword(s):  
Drip Irrigation ◽  
Irrigation System ◽  
Chemical Properties ◽  
Application Rate ◽  
Drip Irrigation System ◽  
Flow Variation ◽  
Agricultural Engineering ◽  
Normal Soil ◽  
Coefficient Of Uniformity ◽  
American Society

Experiment was carried out in the department of Agricultural and Bioresources Engineering, during the period of August to October, 2017. The hydraulic performance of a developed drip irrigation system was assessed. The experimental work was conducted on field with irrigated field area of 7 m x 3 m and lateral spacing was 0.35 m. Sixty (60) hospital drip sets (given sets) were used for the experiment as improved emitters. Volumetric method was used to determine application rate (PR) and emitters discharge. The emission uniformity, emitter flow variation, co-efficient of uniformity and co-efficient of variation were determined accordance with the equations described by the American Society of Agricultural Engineering (ASAE). Soil chemical properties were determined accordance with the American Public Health Association (APHA). The findings revealed that the soil in the area is classified as sand clay loam and normal soil. Results indicated that the mean and standard deviation of the emitters were 9.639 L/hr and 0.07 L/hr respectively. There were no emitters clogging. The emitter flow variation was 2.5 % and less than 10 % which was desirable range, while coefficient of variation was 0.07 and less than 0.11 which was marginal. The application rate was 17 mm hr-1 which was within the recommended range of 15 – 25 mm hr-1. The emission uniformity and coefficient of uniformity were 99.4% and 99.2% respectively, which shows that the system was well-designed. This finding indicated that hospital drip sets proved to the high quality. Therefore, it can be used as standard emitter.

scholarly journals Cyclic Sprinkler Irrigation and Pre-irrigation Substrate Water Content Affect Water and N Leaching from Containers

1994 ◽  
Vol 12 (4) ◽  
pp. 198-202
Author(s):  
Nabila S. Karam ◽  
Alexander X. Niemiera
Keyword(s):  
Water Content ◽  
Irrigation System ◽  
Sprinkler Irrigation ◽  
Application Rate ◽  
N Leaching ◽  
Time Interval ◽  
Water Application ◽  
Total N ◽  
Continuous Irrigation ◽  
Continuous Application

Abstract A series of sprinkler irrigation experiments were conducted to determine the influences of water application rate (WAR), pre-irrigation substrate water content (PSWC), and cyclic irrigation on water and N leaching from container-grown plants. Prior to experiments, Marigold (Tagetes erecta L. ‘Apollo’), were glass house-grown in pine bark-filled 3.8 liter (1 gal) containers. Prior to treatment, substrate was dried via evapotranspiration (ET) to targeted PSWCs. A simulated overhead irrigation system applied the daily water allotment in a single continuous application or cyclically (multiple applications); in most cases the respective ET volumes were applied to the substrate. Water application efficiency (WAE; water vol retained in substrate + water vol applied to substrate) was determined, and in some experiments, leachates were analyzed for EC, NO3-N and NH4-N. A negative linear relationship existed between WAR and WAE. Leachate NO3-N and NH4-N concentrations were unaffected by WAR, however, total N leached increased with increasing WAR. WAE of cyclic irrigation was 4% higher (absolute basis) than with continuous irrigation; WAE increased as the time interval between cyclic applications increased from 20 to 60 min. Regardless of how water was applied, WAE was inversely related to PSWC and application volume. These experiments showed that the most effective method to increase WAE is to irrigate at relatively low PSWCs; if irrigation occurs at relatively high PSWCs, then relatively low volumes should be applied.

scholarly journals Economic viability of retrofiting emitters in center pivot irrigation systems

2012 ◽  
Vol 32 (3) ◽  
pp. 602-608 ◽  
Author(s):  
Cornélio A. Zolin ◽  
Rubens D. Coelho ◽  
Janaina Paulino ◽  
Marcos V. Folegatti
Keyword(s):  
Decision Making ◽  
Irrigation System ◽  
Potato Crop ◽  
Economic Viability ◽  
Water Application ◽  
Economic Perspective ◽  
Sale Price ◽  
Irrigation Systems ◽  
Uniformity Coefficient ◽  
Center Pivot

Although several studies have been conducted to evaluate the uniformity of water application under center pivot irrigation systems, there are few studies concerning the economic perspective of such coefficient. The aim of this study is to present a methodology to accomplish an economic analysis as support for the decision-making to retrofit emitters in center pivot irrigation systems, and to attribute an economic meaning to the uniformity coefficient of water application taking into account the response function productivity to the amount of water applied and the sale price of the crops. In the hypothetic calculation example considering the variation of revenue of potato crop under center pivot irrigation system, it was verified that the area with uniformity coefficient of water application of 90% brought an income increase of BR$ 1,992.00, considering an area about 1,0 ha. Thus, it can be concluded that the methodology presented has met the objectives proposed in the study and made it possible to attribute an economical meaning to the coefficient of water uniformity application.

scholarly journals Centre-pivot irrigation system design for uniform water application rate

2020 ◽  
Author(s):  
Giorgio Baiamonte ◽  
Mustafa Elfahl ◽  
Giuseppe Provenzano
Keyword(s):  
System Design ◽  
Irrigation System ◽  
Design Procedure ◽  
Application Rate ◽  
Water Application ◽  
Irrigation Systems ◽  
Flow Rates ◽  
Irrigated Area ◽  
Application Rates ◽  
Irrigation System Design

<p>In the last few decades, the use of centre-pivot irrigation systems has significantly increased, since it makes farming easier, is more efficient and less time-consuming compared to the other irrigation systems. Several studies have been focused on the hydraulics of the centre-pivot systems. Standard high-pressure impact sprinklers or low-pressure spray sprinklers or Low Energy Precision Application (LEPA) systems are generally mounted on the pipeline.</p><p>To ensure the uniformity of water application, the centre-pivot design requires increasing the flow rates along the lateral, because the sprinklers farther from the pivot move faster, and therefore their instantaneous application rates must be greater. Thus, the irrigated area under a centre-pivot system expands substantially with increasing system length. To irrigate the increased area by maintaining constant the application intensity, the manufacturers propose: i) to increase the flow rates of equally spaced sprinklers, ii) to gradually decrease the spacing of equal-flow sprinklers along the centre-pivot lateral, and iii) to use semi-uniform spacing, which is a combination of the first two methods.</p><p>However, the most common centre-pivot systems have equally spaced sprinklers with increasing flow rates (nozzle sizes) along the lateral, which is probably the easiest method from a practical point of view. Although many definitions and design procedures can be found in the technical literature, a universally accepted design procedure has not yet been found. In fact, the issue of centre-pivot irrigation system design is widely debated and there is still a need for simple, yet adaptive designing guidelines for farmers using these systems, specifically to maximize water use efficiency.</p><p>This study presents an alternative design procedure of centre-pivot irrigation system allowing to set favourable water application rates. First, the sprinklers’ spacing distribution corresponding to a fixed irrigated area along the radial direction is derived. According to this outcome, the results showed that sprinkler characteristics and/or pipe diameter need to be varied along the lateral, based on the desired and uniform water application rate. Then, for a practical case, an application based on the proposed hydraulic design procedure was performed and discussed.</p>

Modification of Water Application Rates and Intermittent Control for Sprinkler Frost Protection

2018 ◽  
Vol 61 (4) ◽  
pp. 1277-1285 ◽  
Author(s):  
Yongzong Lu ◽  
Yongguang Hu ◽  
Chen Zhao ◽  
Richard L. Snyder
Keyword(s):  
Control Strategy ◽  
Irrigation System ◽  
Sprinkler Irrigation ◽  
Application Rate ◽  
Intermittent Control ◽  
Water Application ◽  
Modified Model ◽  
Irrigated Area ◽  
Frost Protection ◽  
Tea Field

Abstract. To validate the feasibility of an automated frost protection sprinkler system, a sprinkler irrigation system with an optimal water application rate was designed, constructed, and tested in a tea field. A modified calculation model of the water application rate was provided by simulation with different values of airflow velocity, air temperature, air humidity, and spray water temperature. An intermittent control strategy was provided using a modified model that included the start and stop time of the system and adjustment of the water application rate. Tea field experiments were conducted to evaluate the effect of frost protection based on this control strategy during frost night events. The results showed that a variable water application rate was better suited for frost protection, and the modified intermittent control automatically regulated the water application rate. In early spring and winter heavy frost nights, the canopy temperature (Tc) of the irrigated area remained above -1.2°C and 0°C, respectively, which is higher than the critical damage temperature for tea plants. The Tc of the irrigated area was approximately 2.8°C higher than that of a non-irrigated area. Moreover, the irrigated area with the modified model had a slower temperature rise after sunrise compared with the non-irrigated area, which was beneficial for frost protection. This sprinkler control strategy is an effective frost protection method that could be applied for in tea fields in the Yangtze River region. The calculation and simulation procedure of the water application rate would be applied for constructing sprinklers for different micrometeorological environments. Keywords: Frost protection, Intermittent control, Spraying water temperature, Sprinkler irrigation system, Tea, Water application rate.

scholarly journals Cold Protection of Leatherleaf Fern in Shadehouses Using Water and Crop Covers

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 808A-808
Author(s):  
Robert H. Stamps
Keyword(s):  
Irrigation System ◽  
Application Rate ◽  
Water Application ◽  
Crop Water ◽  
Irrigation Systems ◽  
Application Rates ◽  
Weight One ◽  
Frost Protection ◽  
Rumohra Adiantiformis ◽  
Supply Water

Six shadehouses were used in tests of irrigation rates and crop covers for cold-protecting leatherleaf fern [Rumohra adiantiformis (Forst) Ching]. Each shadehouse was equipped with two irrigation systems—one over-the-crop to supply heat and one over-the-shadehouse to supply water for sealing the openings in the shade fabric with ice. The over-the-crop irrigation system consisted of frost protection wedge-drive impact sprinklers providing water application rates of 0.30, 0.56, and 0.76 cm/h. Six-m × 9-m spunbonded polypropylene crop covers weighing 20 and 51 g·m–2 were tested. During radiation freezes, all water application rates protected immature fronds from damage. Damage during advective freezes decreased with increasing water application rate, but, even when crop covers were used in conjunction with irrigation, some damage still occurred. Temperatures under the lighter-weight cover were higher than under the heavier-weight one, probably because more water passed through the lighter cover to the crop. Water application rates had no effect on frond yield.

Sign in / Sign up

Export Citation Format

Share Document