نشریه مهندسی آب
سال نهم شماره 2 (تابستان 1400)

Due to population growth, shortage and severe limitation of water resources, one of the basic steps in water management and planning is reservoir optimization. In the present study, after the introduction of the Gray Wolf optimization algorithm, the performance of this algorithm alone and in combination with the genetic algorithm in optimizing the operation of the Taleghan Dam reservoir has been evaluated. The objective function is to minimize the total squares of relative deficiencies in allocating to it each month and maximize reliability throughout the 11-year transition period from 2009 to 2017. Also, the constraints of reservoir continuity equation, reservoir storage volume and reservoir release volume were applied to the objective function of the problem. The results obtained from the performance evaluation indices of the models showed that in terms of time reliability, vulnerability and sustainability indices, the gray wolf-genetic hybrid algorithm with 72.73, 0.28, 24.66 is better than the gray wolf algorithm with 68.93, 0.29, 21.48 and the algorithm. Genetics with 66.66, 0.41, 21.34.

Construction on rivers is inevitable to communicate and reduce costs quickly or to control and control the floods. But the construction of hydraulic structures that are directly exposed to flood currents is not possible only by relying on the assessment of the capacity of structures and their analysis solely on the basis of the principles governing the solid mechanics and should be in addition to the structural examination, the impact of issues. The environment is also examined on structural stability. Estimation of maximum flow around the bridge base with semi-experimental relationships is not a reliable method. One of the methods for recognizing the erosion process is the flow of the flow structure. In this research, the three-dimensional simulation of the steep base is discussed. For this purpose, using the compass software that has a three-dimensional flow model was used to simulate the turbulent flow pattern around the bridge base. To verify the software, the study pattern was performed around the steep base. The simulation results have a good match with real results, which represents the high capability of the simulation model in predicting the steep base.

One of the most important issues in the field of scientific computational hydraulic aspects of the river is the routing of permanent and non-permanent flows. Investigation of flood zoning with different return periods can be named as one of the most important issues in the field of flood management. In the present study, using HEC-RAS software, the flood susceptibility of the downstream areas due to the occurrence of the probable maximum flood in Ghare Aghach dam has been investigated. The research results are displayed in the RAS Mapper environment. The results showed that contrary to what was thought, due to the fact that the overflow of Ghare Aghach dam has been controlled based on the highest probable maximum flood; so this flood will not cause failure in Ghare Aghach dam of overtopping type. The maximum flow from the dam overflow occurred 435 minutes after model simulation and is 171.72 cubic meters per second. According to the results of the Google Earth model, the flooding area of the downstream areas when has reached its peak flow; it is approximately equal to 5.73 square kilometers. The radius of flooding at the moment when has reached its peak flow relative to the coastline, around the villages of Mehrgerd and Hosseinabad is equal to 196 and 1858 meters, respectively. The main residential areas around the villages of Mehrgerd, Hosseinabad and Kasgan Sofla are approximately 60, 587 and 689 meters away from the coastline with the water flow obtained during the peak flow time, respectively.

Then, sampling of erosion and runoff threshold in 6 points with 3 replicates and in different rainfall intensities of 0.75, 1 and 1.25 mm/min in three land uses of the range, residential area and agricultural lands with the help of the rain simulator was done. In addition, the same number of runoff and erosion threshold samples, sampling of the soil physical properties such as clay, silt, sand, very fine sand and moisture content was done. I The results showed that in Gachsaran Formation and in all three rangeland, agricultural and residential land uses and in all three intensities of 0.75, 1 and 1.25 mm/min, very fine soil sand in eight cases had the opposite relationship and in one case had a direct relationship with the erosion and runoff simultaneous threshold and soil clay had the opposite relationship in two cases and had a direct relationship in seven cases and soil silt had the opposite relationship in four cases and had a direct relationship in five cases. Soil sand in six cases showed the opposite relationship and in two cases showed a direct relationship and in one case did not show a relationship, and soil moisture in seven cases showed an inverse relationship and in two cases showed a direct relationship with erosion and runoff simultaneous threshold.

Cultivation of agricultural products faces various constraints such as climatic constraints. In any climatic and geographical conditions for the cultivation of different crops requires a preliminary study of suitable cultivation conditions and location. The main purpose of this study is to identify areas prone to sunflower cultivation in the Dez Basin. For this purpose, after determining the study area, the effective factors in plant cultivation were determined using library resources and the opinions of experts. Then the effect of each factor on the yield of sunflower plant was determined using AHP method. In order to locate and zoning the potential points of cultivation in the study area, a ordinary kriging model was used in the ARC GIS software environment. The results of data processing showed that 29.5% of the basin lands are in a very suitable range, 69% in a suitable range and 1.5% in a suitable medium range for sunflower cultivation.

Studies on hydraulic structures, especially around the bridge bases, show that one of the main causes of bridge destruction is the local turbulence of the flow. In order to be economical and reliable design, you have to get the maximum depth of deflection around the bases. Estimating the maximum depth of scouring with the purpose of determining the depth required for bridge bridges is necessary, as otherwise it may lead to bridge collapse. SSIIM software is used in this study, which takes into account the flow and sediment equations in a three-dimensional fashion. In this software, the flow field is obtained from the Navier-Stokes equations and the K-ε turbulence model, and then, using the nondetective solution of the deposit field and the continuity equation, the ground level changes are calculated around the bridge's base. Comparison of the results shows that the scour depth increases with increasing height, and if the angular gradient exceeds a limit, then the destruction of the wall of the scouring cavity is accompanied.