For flood protection infrastructure to be designed effectively, it is essential to accurately assess the maximum discharge ( Q max ) in Algerian wadis and watercourses. In the absence of direct field measurements, reliance on foreign methodologies is common. However, these methods often overlook the specific characteristics of hydrological systems in Algeria leading to significant inconsistencies and complicating methods choice. Accordingly, the crucial question that arises is: which methodology provides the most reliable ( Q max ) estimates for the purpose of designing effective flood defenses? Therefore, this paper explores the estimation of maximum discharge in Wadis when direct flow rate data is unavailable. The proposed model, outlined in equation (3), is developed through statistical modeling and incorporates key factors such as watershed area (A) and rainfall intensity ( P tc ). The model correlates with observed discharge values by utilizing data from Algeria’s National Water Resources Agency, covering 60 Wadis across diverse regions. This approach outperforms existing models, achieving a notably low mean normalized error of 10%, signifying substantial improvements in accuracy.
Abstract Irrigation development focused on implementing ecologically sound and nature-based solutions was explored. This approach is crucial in addressing the pressing need to conserve water and electricity resources, aligning irrigated farming practices with current global challenges and sustainable development goals. Unlike traditional methods, it is essential to view water and electricity resources as integral components of irrigation efficiency from a resource-ecological perspective. A computer experiment involving predictive and simulation modeling was conducted to assess the feasibility and potential cost savings of adopting resource-ecological principles in irrigation practices. The study evaluated the resource-ecological efficiency of different sprinkler irrigation regimes based on irrigation reliability, which measures deviations from projected irrigation and watering rates. Multicriteria regression analysis revealed a strong correlation ( R 2 = 0:874) among various factors influencing irrigation efficiency. Results indicated that implementing different levels of irrigation reliability could significantly improve technological efficiency, with crop productivity reductions ranging from 10.80% to 18.06% and water and electricity cost savings of 27% to 48%. These findings support the integration of nature-based and ecologically effective irrigation solutions to promote sustainable agriculture in the face of global challenges such as climate change, water scarcity, food insecurity, and energy shortages.
Abstract This study presents the use, and its advantages, of artificial intelligence methods to predict the discharge coefficient (Cw ), considering the approach conditions of the labyrinth weir type D. The study suggests modifying the training and validation rates in AI tools, which are often fixed without proper justification in previous studies. Unlike most studies that use geometric dimensions as inputs, this work focuses on the approach conditions (the emplacement of the labyrinth weir and filling the alveoli upstream and downstream) of the labyrinth weir type D. The results, based on laboratory experiments, show that these modified inputs significantly impact the e ciency and cost of constructing the weir. Moreover, the C w predictions based on these inputs are highly satisfactory compared to laboratory test results. In terms of training and validation ratios, the study confirms that the optimal ratio is 70/30 for accurate and highly satisfactory predictions.
Abstract Desirable conditions of airflow should be provided for spillway chute aerators in two-phase air-water flow, especially in large-width chutes. There is no general approach to determine air entrainment, concentration distribution, and submergence along a chute introduced by an aerator shaft. The two-phase air-water modeling of Gavoshan dam in Iran as a case study of chute flow, its aerator, and the characteristics of flow into the cavity formed below the jet have been numerically investigated, and the results obtained have been validated against the laboratory experiments. The hydraulic parameters of the cavity and aerator shaft were determined to evaluate their performance and emphasize the importance of a proper aerator design. Sections with a greater distance from the bottom of the chute exhibit higher pressure magnitudes, while the mean air concentration values in the cavity are smaller in sections close to a ramp. Higher water discharge, lower pressure head in sections near the bottom of the cavity, and lower air concentration in sections near the ramp into the cavity increase the probability of cavitation occurrence.
Abstract The determination of resistance coefficients, such as Chezy’s or Manning’s coefficients, requires a great deal of sensible thought in order to express these coefficients better and more extensively in free-surface channels and aqueducts. This can be achieved if the expression of the resistance coefficient is well stated and takes into account the maximum number of parameters for governing flows in channels. However, in most practical cases, if these coefficients are not expressed by implicit models, they are generally taken as constant and arbitrary. To this end and in a rational manner, the dimensioning and design of channels requires the expression of the resistance coefficient in an easily and explicit form by adopting numerous flow parameters, namely the roughness of the walls, the aspect ratio, the slope of the channels and essentially the viscosity of the liquid. To achieve this aim, the Chezy’s resistance coefficient C is identified using the rough model method (RMM), which gives the discharge under uniform flow conditions appropriate to a round-cornered rectangle channel.
