Sustainability of water supply networks should be based on the risks of water hammer phenomenon. ... more Sustainability of water supply networks should be based on the risks of water hammer phenomenon. The purpose of this study is to provide a new approach to the analysis of water hammer phenomenon in the water supply network. By conventional methods, the damage because of water hammer is estimated based on the maximum pressure at nodes. However, during this phenomenon continuation and changing of water hammer in overtime is ignored. In this study, quantitative parameters, to evaluate the network performance will be assessed under the water hammer phenomenon. Hence, the information through the parameters of reliability, resilience, vulnerability and their composition, sustainability parameters are analyzed. However, numerical analysis of water hammer phenomenon caused by sudden pump stop was done using HAMMER software. The results showed that the sustainability parameter can be used to evaluate the efficiency of water networks. In the event of water hammer phenomenon 4.83 percent of po...
In this research dense fluid discharge was experimentally investigated under the surface jet in t... more In this research dense fluid discharge was experimentally investigated under the surface jet in the shallow acceptor. The investigated parameters were depth of the acceptor ambient, flow rate and the concentration of surface jet. In order to investigate the relationship between these parameters, a physical model experiments were performed in the hydraulic laboratory of Shahid Chamran University. The results showed that progressive length of the surface jet core is directly proportional to Froude number of fluid density, and is inversly proportional to fluid density concentration. Besides, the progressive length of the jet core increases with increasing the depth of the acceptor ambient. This length increase is due to the decrease of water surface tension. In average, increasing the depth of acceptor ambient twice, the progressive length will increase 38%, and its increasing three times, will increase progressive length of jet core 62%. Besides, in the relationship obtained for the progressive length of jet core R 2 is 0.94.
s: Investigating the features and flow behavior and related component is one of the complex pheno... more s: Investigating the features and flow behavior and related component is one of the complex phenomena that make using of software inevitable. Groin is simple hydraulic component that used for organizing the rivers in bend or direct way and erosion control and protecting of shores. In this project by using Flow-3D software, the numerical model of flow pattern was prepared around a groin. This research with applying different model of turbulence flow, including various Froude numbers and by setting 4 L-shaped single groins with charging john angle in 4 situation of 30,45,60,75 degree related to flow direction in 180 degree bend and 18,20,22,25 lit/s discharges and constant depth of 12cm in clear water conditions, has studied the effect of these model on flow speed changes by second flow and vortex flow around groin. this investigation showed that range of maximum speeds and vortex flows and scouring were occurred in maximum amount in 75 and in minimum amount in 30.in different degrees...
Lopac gates, with the benefits of easy installation, automation and the ability to pass sediments... more Lopac gates, with the benefits of easy installation, automation and the ability to pass sediments and floating objects, are among the new structures considered for water level regulation and flow control in the irrigation canals. Converting the shape of the gate from a rectangular one to an elliptical one allows the flow rate to be increased by the same water level. In the present study, the effect of the sudden transition on the discharge and energy dissipation of the elliptical-lopac gate (ELG) in the submerged flow conditions was evaluated in the laboratory. The results showed that the dimensionless discharge and energy dissipation of the ELG with sudden transition to channel width conditions was decreased by 28 to 86% and increased by 11 to 35%, respectively. Finally, the statistical equations were presented to estimate the dimensionless discharge and energy dissipation of ELG by sudden transition under submerged flow conditions with a maximum error of 16%.
Determination of Soil Compression Index, CC, in Ahwaz Region
Construction of hydraulic structures or other structures compact the soils layers and create hydr... more Construction of hydraulic structures or other structures compact the soils layers and create hydrostatic pressure (excess pore water pressure) in saturated fine grained soils. While the excess pore water pressure dissipates, stresses on the soil skeleton (effective stress) gradually increase; thus soil undergoes deformation or strain in vertical direction (consolidation settlement). By the use of compression index, Cc, which is obtained from consolidation test, one can estimate the among of field settlement. These expressions correlate Cc to the soil properties or physical indices such as Atterberg limits, void ratio and specific gravity. In this research we have attempted to find some expressions for the soils of Ahwaz region. To do this, consolidation tests and tests for determination of soil physical properties and Atterberg limit have been carried out on 29 undisturbed samples which were prepared from different locations and depths.. The results showed that there is a good correlation between Cc and initial void ratio.
Evaluation of Karun River Water Quality Scenarios Using Simulation Model Results
Karun River is the largest and most watery river in Iran. This river is the longest river which l... more Karun River is the largest and most watery river in Iran. This river is the longest river which located just inside Iran and Ahvaz Metropolis drinking water supplied from Karun River as well (fa.alalam.ir). Karun River as the main source of water treatment plants in Ahvaz, like most surface waters affected by various contaminants which caused changes in water quality of the river (www.aww.co.ir). Causes such as constructing several dams at upstream river, withdrawal of water from the upstream to the needs of other regions of Iran, exposure of various industries along the river and discharge of industrial and urban sewage into the river, seen that today this river is deteriorating rapidly, qua today is the depth of river reach to 1 m with a high concentration of pollutants (www.tasnimnews.com). In this study, considering the quality parameters, by using the QUAL2K model and with regard to water quality standards of defined classification, we defined various scenarios. Then two parameters, BOD and DO were chosen as indicator parameters for assessing these scenarios. Model was calibrated to data from spring 2012 and validation was performed by winter and spring 2013. Then the model was used to take management decisions for critical situation. The results showed that by changing in location of entry pollutant in the river we achieved water environmental goals. This scenario is also useful for future that flow of river reduced.
Evaluation of strength parameters of stress-strain development in clay soil and clay-sand soil
Soil strength and elasticity modules are important parameters in the soil engineering. Elasticity... more Soil strength and elasticity modules are important parameters in the soil engineering. Elasticity module shows the potential of soil deformation. In this research, samples of problematic clay soil and stabilized clay soil with sand, were provided and investigated. The samples were built in various moistures and different compactions, and then those in unconfined set were tested. The moisture in these experiments are, optimum wet content, 2% less than of this, 4% less, 2% more than of this and 4% more. The applied compactions, R.C, are equal to 85, 95 and 100 percent. Using data gathered, the soil axial strengths and elasticity modules were calculated. Findings show that for entire samples in clay and sand-clay, increase of moisture leads to decrease of the soil axial strength. Nevertheless, the decreasing intensity of soil strength in sand-clay is more than the problematic clay soils. Results of the experiments show that the change of wet content from 4% less than optimum moisture to 4% more, decreases soil axial strength of problematic clay soil, to approximately 84%, while, this amount for sand-clay soil is about 93 percent. Moreover, the decrease of elasticity module in sand-clay samples with 100% compaction and 13% wet content is approximately 51 percent.
Determination of Soil Compression Index, Cc, in Ahwaz Region
Construction of hydraulic structures or other structures compact the soils layers and create hydr... more Construction of hydraulic structures or other structures compact the soils layers and create hydrostatic pressure (excess pore water pressure) in saturated fine grained soils. While the excess pore water pressure dissipates, stresses on the soil skeleton (effective stress) gradually increase; thus soil undergoes deformation or strain in vertical direction (consolidation settlement). By the use of compression index, Cc, which is obtained from consolidation test, one can estimate the among of field settlement. These expressions correlate Cc to the soil properties or physical indices such as Atterberg limits, void ratio and specific gravity. In this research we have attempted to find some expressions for the soils of Ahwaz region. To do this, consolidation tests and tests for determination of soil physical properties and Atterberg limit have been carried out on 29 undisturbed samples which were prepared from different locations and depths.. The results showed that there is a good correlation between Cc and initial void ratio.
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