M. J. Monem, M. R. Alirezaee, E. Salehi,
Volume 6, Issue 4 (1-2003)
Abstract
Recent studies have shown poor performance of irrigation systems, which indicates the requirement for special attention to performance improvement. The first step for improving the performance of irrigation systems is evaluation of the present situation. Performance evaluation methodologies presented so far are either qualitative such as DA (Diagnostic Analysis), RA (Rapid Appraisal) and FA (Framework Appraisal), or they are similar to classical methods even if they produce quantitative indicators. They fail to introduce performance standards. In this study, using Data Envelopment Analysis (DEA), which is a quantitative method and produces realistic standards, 8 irrigation systems were evaluated and their performances were determined. With respect to the number of decision-making units, inputs, outputs, and corresponding returns to scale for irrigation systems, a suitable DEA model was selected. Capabilities of DEA allow for separate treatment of performance evaluation of overall irrigation network and its operating company. This feature is implemented using different technical and operational indicators.
The results indicated that Zayandeh Rood irrigation system, among the 8 irrigation systems, has the highest technical efficiency. Minab and Varamin systems have the lowest technical efficiencies. Golestan and Behbahan Networks perform well, although their operating companies are inefficient. Garmsar, Ghazvin, and Moghan systems, although not inefficient, have some improvement potentials. In general, with respect to the capabilities of DEA in performance evaluation of irrigation systems and indicating appropriate standard, it can be concluded that this technique is quite efficient and successful for performance evaluation and improvement of irrigation systems.
Sh. Zamani, A. Parvaresh Rizi, S. Isapour,
Volume 17, Issue 66 (2-2014)
Abstract
Modernization of irrigation canals as an operation improvement tool is essential to promote the performance of canal networks and indeed requires control systems. Proportional integral derivative (PID) algorithms have more applications than the other controllers in different places of the world, but tuning these controllers for different hydraulic conditions of canals is considered as a major problem for designing control algorithms. Since the bottom slope is one of the effective factors in the water flow dynamic behavior, in this research, the distant downstream Proportional Integral Derivative feedback control with decouplers was designed with a change in longitudinal slope in a reference canal and its performance was investigated. The canal characteristics were used to tune this controller and the system identification as a new method was applied for determining canal characteristics. SOBEK hydrodynamic model modulated with MATLAB software was used to design and run the control algorithms, and slope influence on water flow behavior, tuning controller, and coefficients of controller were investigated with different values of slope. Then, controller performance for hypothetical period of operation in various scenarios was evaluated with computation performance indices. The results showed less resonance behavior of water flow and less potential of controller in steep slope
B. Moumeni, M. Masoudian, M. A. Gholami Sefidkohi, A. Emadi,
Volume 22, Issue 3 (11-2018)
Abstract
Over the years, since the beginning of the national and infrastructural project of Development and Renovation of Paddy Fields of Iranian Northern provinces, it has been essential to evaluate water distribution and delivery Performance of the project to get its feedback in the pursuit of the desired goals. However, the results of the evaluation of a system can reliable when they are based on quantitative indicators, not on personal opinions and empirical judgment. So, in this study, Total Error (TE) of performance of water delivery system, a statistical indicator, and its component including adequacy, water management capability and equity errors were calculated and compared for two concrete and earthen irrigation canals. This analysis was done based on calculating water demand and measuring the volume of delivered water between outlets during the irrigation season in the paddy fields of Esmaelkola of Joybar city, in 2015. According to the results, although the concrete channel (0.28) had less error than the earthen channel (0.43) and in the concrete channel, as compared to the earthen channel, the share of the components of adequacy and water management capability from the total error was dropped from 47% to less than 10%, but the error in the water delivery of the concrete channel was still high due to the error in the equity of distribution, whose value was 0.25 (90% of the total error). Therefore, in order to reduce the performance error, after channel lining, it would be necessary to make fundamental changes in the intake and flow control structure in addition to the training of irrigators regarding water delivery based on water demand.
