فصلنامه مهندسی منابع آب
پیاپی 43 (زمستان 1398)

Farm experiments are useful in knowing the drainage systems but they have considerable limitations including the inability to use them as prediction tools. Application of simulation models can cover these deficiencies but it is necessary to use the field data to evaluate the accuracy of the model. In this study, Particle Swarm Optimization Algorithm and Genetic Algorithm is used to predict hydraulic head. For this purpose, field R9-11 of the Debal Khazaei sugarcane plantation is selected and number piezometers were installed in different depth (2/2,3,4 and 5 meters from the ground) and distance from collector.Piezometers. hydraulic load changes, the volume of irrigation water and drainage flow were measured from September 2013 to November 2014 on a daily basis. The results showed that the Particle Swarm Optimization Algorithm has a highest accuracy in predicting hydraulic head. So that the average RMSE in different depths between measured and predicted with Particle Swarm Optimization Algorithm and Genetic Algorithm obtained 0.098 and 0.114 , respectively and the average coefficient R^2 in different depths for Particle Swarm Optimization Algorithm and Genetic Algorithm models obtained 0.991 and 0.94 respectively. The test results of the comparison between measured and simulated data show that, between any of the values predicted by the models, measured data were not significantly different.

In this paper, the physics of passed flow on submerged vane that placed at the bottom of different kinds of channels is studied. Also it presente the effects of: changing angle’s vane, the distance of vane from wall and the situation of vane in front of the lateral intake on the physics passed flow on submerged vane. In this order we use the fluent software to simulation flow pattern around the submerged vane at the bottom of straight channel, U shape channel and U shape channel whit lateral intake. The results show that when the vane placed at the bottom of the straight channel with angle of 20 degree 2 vortex by same direction at both side of the vane is created. By changing the vans angle from 20 to 40 degree, one smaller vortex with opposite direction near the bottom and close the trialing edge is created. This vortex is horseshoe vortex. By using vane in U shape channel, the vortex’s direction which is created by the vane,become greater than past. This subject show that workability of the vane in U shape channel is better than in straight channel. Horseshoe vortex’s formation close the trialing edge depends on the high angle of attack. In U shape channel with lateral intake vortex is smaller because of the suction that is made by lateral intake.

Excessive use of fossil fuels, the increasing world population and the ever-increasing of industrial activities accordingly to provide welfare and the needs of humans, thereby has been increased the concentration of greenhouse gases, particularly carbon dioxide in recent decades. This increase in greenhouse gases cause a phenomenon called climate change. The purpose of this study was to investigate the effect of climate change on the output of three CANESM2 MPI-ESM-MR and CCSM4 models selected from the CMIP5 model series in the near future (2020-2020) and the future of the future (2070-2099). ) Under the RCP2.6, RCP4.5, RCP8.5 radiation induction scenarios on precipitation, minimum temperature and maximum temperature. To simulate the climatic parameters of the Zarrine River basin, the data of these three models were microscopically compared with the LARS-WG model. According to the evaluation statistics, the MPI-ESM-MR climatic model has better performance than other two models for simulating climatic parameters. Subsequently, by examining the results for all stations, the temperature trend with increasing and precipitation decreased. Saqez Station showed a more intense trend in simulation as the temperature in this station is increased by an average of 0.5 to 1 ° C higher than the Takab station and in the rainfall, with a decrease of 3 to 30 mm, the ratio Shows Takab. Also, the minimum temperature is higher than the maximum maximum temperature at all stations.

Hillslopes of natural catchments have a complex geometry. In complex hillslopes, the plan shape (convergence, parallelity and the amount of profile curvature (concave, straight and convex) create nine different shapes of complex hillslopes. To examine the amount of surface and subsurface runoff of hillslopes based on Dunne-Black mechanism, the saturated and unsaturated zones of hillslopes must be first separated. Travel time of surface and subsurface flow is a key parameter in runoff prediction of most rainfall-runoff models like time-dependent hydrograph models. In this research, a new simple saturation model, called Gamma, was employed with simpler geometry and equations. In this model, analytical equations were introduced to calculate saturation zone length (SZL) and subsurface travel time (STT). Results of Gamma saturation model and travel time of the proposed model were compared with other complex saturation models like W model and Sigma model by using two criteria of root mean square error (RMSE) and Nash efficiency factor (CE). The mean of RMSE for SZL prediction according to Gamma and Sigma models are 0.84 and 0.82 respectively. The mean CE for STT prediction according to Gamma and Sigma models are 0.79 and 0.72 respectively that were evaluated well. The main goal of this study is the examination of the efficiency of three models in estimation of saturated zone length and subsurface travel time. According to the results, Gamma model results were very close to those of Sigma model but for the straight divergent and convex divergent hillslopes, the Gamma model is not recommended.

Despite the many studies that have been done in reservoir exploitation, due to the willingness of researchers to reduce errors in calculations, this issue is still a matter of interest and is of interest to water researchers. In this regard, the use of the capability of Fractional Algorithms Which are generally derived from nature and used in complex problems and optimization problems. In recent years, it has been highly regarded. Therefore, in the present study, the optimal allocation of water resources in the semi-Sistan reservoir reservoirs has been investigated under management scenarios using the Fuzzy Firefighting Technique. The results of the research show that the best value of the target function was 2309/66 million cubic meters. Also, in the early years, the optimal release of firefighting algorithm was obtained at 29.1376 million cubic meters, with a demand of 98.3121 million cubic meters, of which 69.1745 million cubic meters were lacking. The results of the evaluation of various management scenarios showed that if these projects were implemented, the amount of water allocated to the agricultural sector would be significantly reduced. Therefore, it is suggested that with the spread of Iran's legitimate rights from Afghanistan, it will be possible to overcome the dangers and droughts of the last few decades.

In the current situation, we face the limited quantitative and qualitative water resources. We have no choice except to change the perspective towards consumption management. Separating drinking water from sanitary water is one of the components of the quality management of consumption. Two senarios are water harvesting stations and dual water distribution network.The scenarios of separation of drinking and non-drinking water were analyzed using the EPANET software in Safaieh region. The estimated cost of the pilot region showed that the first method was more costly than the second method. The results of the economic analysis of methods of separation of drinking and non-drinking water using the Net Peresent Value (NPV) showed that all methods have positive NPV index, which indicates that the projects are successful economically. In relation to the comparison of the sales price of drinking water, the first method, ie, plumbing to the home with a price of 4700 toman per cubic meter, is higher NPV and more economical than another method. But since other parameters such as the accessibility of people to the drinking water distribution network, the age of the people, public acceptance is important in selection of the best method of the separation of drinking water from non-drinking water. Dual water distribution network method is suggested. By implementing this project can be managed water consumption through the quota of sanitary water and correcting the price of drinking water.

The effects of clear and turbid water on the contribution of prefitons, which play an important role in aquatic nutrition and in the treatment of contaminated waters, are very important in a way that is more abundant in clear waters than opaque waters. In this paper, using Sentinel-2 measuring images and using spectral properties of opaque and clear water, and emphasizing statistical quantities, they are to be detected in the Sefidrud Dam during two seasons (March 27 , 2017) and summer (September 13, 2017). In this regard, after applying the required preprocesses (geometric and radiometer correction), by examining the spectral behavior curve of these two phenomena as well as the OIF index, optimal color combinations were detected by the test and error method. Accordingly, the most suitable color combination contains the largest amount of information for the spring, the color combination (a4,8,8) and for the summer, the color combination (8.1, a8) was determined. On the other hand, using the spectral-velocity study of opaque and clear water, within the range of 4/0 – 87/0 μm (bands 1 through a8), these two phenomena are well-differentiated from each other and other phenomena. Therefore, the NDVI index, which examines the standardized difference of the near-infrared spectral range (band 8) and visible red (band 4), was considered for revealing cloudy and transparent water, and eventually, by applying thresholds on it, Cloudy and clear water was distinguished from each other.

Local scouring around the pier is one of the main reasons for the instability of the bridges. Providing appropriate methods for predicting and controlling scour depth is one of the important issues that have been considered. Various methods have been proposed to control the scouring around the bridge pier. In this study, the effect of using the bed sill on scouring around the cylindrical bridge pier under clear water conditions has been investigated and compared in non-cohesive sediments. The bed sill has been placed at the downstream of the pier and its effect on reducing the scouring has been evaluated by changing distance between and the pier and sill geometry. In this research, a pier with 50 mm diameter was used. The results showed that bed sill setting has effect on scour reducing. Also, the distance and the shape of the sill have the greatest effect on reducing the scour. The placement of the straight and oblique bed sill at the backside of the pier resulted in a decrease of 11% and 16%, respectively, in the maximum of scour depth. By increasing the distance of sill to the oblique pier, its protective effect was reduced. Also the oblique bed sill more reduces the amount of scour around the pier relative to the straight bed sill and prevents the scour hole from developing to upwards.

This study investigated the effects of climatic changes on temperature, rainfall, and runoff in the Doroudzan catchment in the northeast of Fars province, Iran. Temperature and rainfall changes in two future middle and far period downscaled and studied using 15 CMIP3 climatic models, under emission scenarios A2, B1and A1B, from the database of the LARS WG5.5 model. The difference in the amount of variations in temperature and rainfall in the periods and the observational amounts under the 15 models indicated the uncertainty of the changes values. To reduce this uncertainty and limit the results to the management and planning of water resources, an ensemble approach was considered. For the preparation of the ensemble approach, the parameters from the files of the 15- models file scenarios were averaged so that a climatic ensemble model could be obtained for each period. Then, the runoffs of the next two periods were produced using the FEEDFORWARD neural network. The results indicated an increase in the average monthly maximum temperature and the minimum temperature. The results also showed a decrease in the rainfall in the early months of the year as well as an increase in the rainfall in the spring in most scenarios. Generally, results showed a reduction in the average annual rainfall. The maximum amount of reduction was in far future far period. Besides, a reduction occurred in the average runoff of the catchment in the periods, values in the most years.

In this paper, two optimization methodologies for conjunctive operation from surface and groundwater resources are developed. The first proposed methodology consists of an integrated model that is able to consider and analysis supply and water demand management policies, together. In this model, optimum decisions are determined for reservoir-river-groundwater system simultaneous operation for developing water supply and increasing water demands conditions. Also, different climate change scenarios are considered for evaluating the system in the different situations. In this model, using NSGA-II multi-objective optimization model that surface and groundwater allocation are determined with multi-objective goal programming approach for 10-year periods in different climate. For analyzing optimization model, performance criteria are determined for system in the conjunctive operation structure in order to evaluate and rank operation approaches. Finally, using Borda count model, an appropriate solution is chosen on the obtained trade-off among different objectives. In the second methodology, a simulation-optimization model is developed for conjunctive operation from surface and groundwater resooptimum decisions are determined for reservoir-river-groundwater system simultaneous operation under different climate scenarios for developing water supply and increasing demands system. They are presented in the operation rules framework and rule curves in the monthly and weekly time steps. Finally, using fallback bargaining model, an appropriate solution is determined in obtained trade-off among different objectives of stakeholders. The results show that, aquifer modeling has better estimation from water system situation in the case study and the proposed methodologies can determine solution that can provide the most possible compromise among different stakeholders.

muddy flows are gravitational flows, which are the difference in density or difference in weight of unit volume between two fluids due to suspended sediments. Due to the abundance of these streams in nature knowing and studying the characteristics and factors affective it is imperative and unavoidable. The creation of obstacle in the flow path can affect on the muddy flow character such as flow mixing rate and flow density. In this paper by the Flow 3D software the effect of trapezoidal obstacle in the characteristics of the muddy flow especially its mixing rate has been studied. : In order to Verification, results of the this numerical model Were compared with the results of laboratory work Naji Abhari et al. The results showed that the presence of the obstacle caused the kinetic energy of turbulence to increase by almost 1000% more than Without obstacle. the depth-density variation diagram for two channels showed that the current density in channel With obstacle was less than obstacle-free type. also by increasing 1% the height of obstacle, an average of 2% would be added to the turbulence energy and one-percent increase in the angle of entrance prevented an increase of 1.366 % of the energy of turbulence. Simulation for obstacle with different velocities indicates that with increasing the velocity of the pure water, the amount of maximum energy of turbulence and as a result of flow mixing increases.