Pipe Irrigation System Research Articles

Study on Non-Depositing Critical Velocity of Water Delivery in Pipeline System under Different Conditions of Sediment-Laden Water Source

Non-depositing critical velocity is an important parameter in project design for low pressure pipe irrigation system in irrigation districts of sediment-laden water resource. The velocity used to be calculated through the critical velocity equation for solid particles delivery in pipeline system. However, the calculation error is relatively large due to the small sediment content and the large fine-textured particle content. This paper conducted different non-depositing critical velocity experiments under 6 sediment concentrations and 4 pipe diameters. The impacts of sediment concentration, pipe diameter, particle size and distribution on the non-depositing critical velocity of water delivery in pipeline system were analyzed based on the experimental results.

Climate Change and the Performance of Pressurized Irrigation Water Distribution Networks under Mediterranean Conditions

Numerous previous studies have modelled the impact of climate change on crop water requirements and hence future water resource needs for irrigated agriculture. Fewer have considered the impacts on the performance of irrigation systems and the required engineering and managerial adaptations. This study considers the impacts and adaptations for a typical pressurized pipe irrigation system. The dry years of the baseline period (1970–90) in the southern part of Italy are expected to become the average or even wet year by the 2050s, according to HadCM3 projections. Under these conditions, the large water distribution systems designed to satisfy the baseline dry years will fail unless appropriate engineering or managerial adaptations are made. The resilience of District 8 of the Sinistra Ofanto to the possible future increase in irrigation demand has been assessed. A stochastic weather generator was used to generate future weather under the IPCC A1 and B1 emissions scenarios, taking into consideration the outputs of the HadCM3 model. A daily water balance model was used to quantify the actual and future peak water demand of the district. The reliability of each hydrant under baseline and future demand was calculated using a stochastic hydraulic model and the failure zones identified. Under the current design, the system can tolerate a peak demand discharge up to 1,500 l.s−1, which is below the 2050s' average (1,720 l.s−1). Above that value, the performance of the system will fall drastically as the number of unreliable hydrants will increase. In the future, assuming the same cropping pattern, the threshold discharge (1,500 l.s−1) will be exceeded 80% of the time and, as an average, 20% of the system's hydrants will be failing during the peak demand periods. The adaptation options available to farmers and system managers in response to the increasing demand are discussed.

Spring-Operated Semiautomatic Irrigation Valves

ABSTRACT TORSION spring operators for standard low pressure butterfly type irrigation valves are described. These are used with 24-h timers to semiautomate gated pipe irrigation systems and are particularly well suited for use with flow-thru single pipeline systems. They are presently marketed in 150 mm (6 in.), 200 mm (8 in.) and 250 mm (10 in.) diameter sizes.

Technical and economic considerations in the design of closed conduit irrigation systems: A case study

Closed conduit irrigation systems are designed to respond to moisture requirements and permit water application at different required rates. The formulation of these requirements allows the engineer to select one of the many possibilities of the water system layouts. However, the requirement that the cost of the system for a given set of operational conditions should be minimal is not always included in the design because of the difficulties in selecting the most economic layout among the many alternatives. The main parameters characterizing pipe irrigation systems are presented and discussed. A trade-off among the irrigation system components for various layouts is presented in a case study and discussed, emphasizing the complexity of the decision-making procedure.

Cablegation: 11. Simulation and Design of the Moving-Plug Gated Pipe Irrigation System

ABSTRACT THE hydraulics of a moving-plug gated pipe irrigation system are analyzed. A relationship was developed for predicting orifice discharge coefficients for a range of typical pipe flow velocity and head conditions. A simula-tion model was developed to predict the time distribution of orifice flows, the distribution of infiltrated water across a field, and runoff rates. The model can be used to design cablegation systems for fields having variable pipe slopes and variable furrow lengths. Orifice sizes are varied along the pipe line and the plug travel speed is varied in order to obtain optimum net water application for all furrows and to keep the furrow stream sizes within acceptable limits.

Nitrogen Fertilizer from Solar Energy

ABSTRACT IN the spring of 1977, the Massachusetts Institute of Technology and the University of Nebraska engaged in a project to build a 25 kW peak photovoltaic array. This array was used to power an automated gated pipe irriga-tion system and a natural air grain-drying system for a 32 ha corn field near Mead, Nebraska (Romaine, 1979; Fischbach, 1977). Due to the seasonal nature of these loads, they consume only half of the total energy produc-ed annually by the photovoltaic array. In considering possible uses for the remaining energy produced by the array, the University was most interested in finding an agricultural use that contributed significantly to the total farm energy requirement.

Study on the irrigation water distribution system developed by Barind Multipurpose Development Authority

Irrigated agriculture has been playing a vital role for the growth in crop production in Bangladesh. Minor irrigation comprising of shallow tubewells (STWs), deep tubewells (DTWs), hand tubewells (HTWs) and low-lift pumps (LLPs) is a major irrigation system in the country. Poor performance of irrigation is an issue for the expansion of irrigated area. The present study was carried out to examine the conveyance efficiency and rate of irrigation water loss in DTW schemes in Bogra, Thakurgaon and Godagari zones of Barind Management Development Authority. There were various types of water distribution identified in these schemes with including Poly Venyl Chloride (PVC) buried pipe, cement concrete (CC) rectangular, Ferro trapezoidal, Ferro semicircular and rectangular earth drain. The average conveyance efficiency of PVC buried pipe for Bogra, Thakurgaon and Godagari zones ranged from 94.46% to 95.37% and rate of water loss ranged from 5.45% to 9.55% in three study zones. Average conveyance efficiency of CC rectangular for Bogra and Godagari zone ranged from 91.20% and rate of water loss from 6.58% to 9.93%. Average conveyance efficiency of Ferro trapezoid for Bogra and Godagari zone ranged from 87.80% to 90.06% and rate of water loss ranged from 9.94% to 12.21%. Average conveyance efficiency of Ferro semicircle for Bogra and Godagari zone ranged between 88.13% and 86.82% and rate of water loss between 11.59% and 11.68%. Average conveyance efficiency and rate of water loss of rectangular earth drain Godagari zone was 58.66% and 42.29% respectively. About 80% farmers recommended buried pipe irrigation system and about 20% semi-circular channel. The study suggests that the improved water distribution system as developed by BMDA is sustainable to increase productivity of irrigation systems in Bangladesh. DOI: http://dx.doi.org/10.3329/jbayr.v1i2.10032

Discussion of “Unsteady Flow in Open-Type Pipe Irrigation Systems”

Discussion of “Unsteady Flow in Open-Type Pipe Irrigation Systems”

Closure to “Unsteady Flow in Open-Type Pipe Irrigation Systems”

Closure to “Unsteady Flow in Open-Type Pipe Irrigation Systems”