Predicting Sedimentation at Mujib Dam Reservoir in Jordan

Reservoir sedimentation is a severe problem facing dams causing the decrease of active water storage which is the main purpose of the construction of dams. Mujib dam, constructed in Jordan in 2003, was selected to estimate the quantity of sedimentation in its reservoir. Arc-View Soil and Water Assessment Tool (AVSWAT) model was used to simulate Mujib dam catchment area. The results of this study identified the quantity of water and sediment inflow to the reservoir. They also identified the regions of high soil erosion, sediment yield and delivery ratio in order to manage these regions by applying techniques which reduce these values in sequence to decrease the sediment yield reaching the reservoir

Sediment Yield Assessment for Tannur Dam Reservoir in Jordan

Reservoir sedimentation is caused from erosion process in the catchment area, the sediment build up in the reservoir, reduce its capacity and affect the aim for which the dam was constructed. This study presents an application of the Soil and Water Assessment Tool (SWAT) to simulate the water and sediment yield for Tannur dam reservoir in Jordan. The model was calibrated and verified using the monthly average surface flow and sediment measurements at Tannur gauging station. The optimum curve number (CN) was found in the range 82 to 86 and land cover factor (C) in range 0f 0.003 to 0.03. Model validation results estimated the total volume of water of 110.5 MCM and total amount of sediment yield of 0.8 million ton reached Tannur dam reservoir during the period from October 2003 to December 2009. Total sediment yield of 2.5 million ton was predicted for the period 2010-2030. Subbasins 14 and 30 are more susceptible to soil erosion and sediment yields. The present work could assist in quantifying sediment yields in the long-term as well as in identifying the most susceptible areas within the catchment in order to assist policy makers in taking cost-effective management decisions. Keywords: Sediment yield, Erosion, Reservoirs, Tannur dam, Jorda

Groundwater Recharge from Wala Dam Reservoir in Jordan

A simulation model is presented to investigate the interaction between the surface water reservoir behind Wala dam in Jordan and the groundwater aquifer in the area. MODFLOW software with RES package is used with the available measured data to calibrate the aquifer parameters (transmissivity, specific storage, specific yield, and vertical hydraulic conductivity of the reservoir bed). Steady and transient verification processes will be conducted. Two scenarios are studied to predict the quantity of groundwater that can be pumped from Heedan wells to Amman. This study will show the benefit of natural recharge from surface water to groundwater and the rate of pumping water to Amman can be raised to five times the rate before the dam construction.

Role of Leukotriene in Gastric Ulcer Induced by Acetyl Salicylic Acid in Male Rabbits : Gastroprotection by Montelukast

Gastric mucosal damage is a common disorder of the gastrointestinal system. Non- steroidal anti-inflammatory drugs (NSAID) are known to be aggressive agents for gastric ulcer development. Leukotrienes  play an important role in gastric mucosal damage induced by NSAIDs. Montelukast , a selective reversible Cysteinyl leukotriene receptor 1 antagonist, was reported to have beneficial effects in management of experimental gastric mucosal ulceration. This study designed to evaluate  the role of leukotriene against acetyl salicylic acid-induced gastric mucosal damage and to evaluate the gastroprotective activity of montelukast . Thirty local domestic male rabbits had been used in this study , divided into five groups as follows: normal control group, acetylsalicylic acid ( ASA) treated group, Omeprazole pretreatment group, montelukast pretreatment group, montelukast alone  treatment group. At the end of the experiment, the stomach of rabbit  is removed to prepare the tissue homogenate .  The results revealed that after administration of ASA significantly increase the mean ulcer index along with the LTD4 concentration, LTB4 concentration . But in presence of  montelukast  there is a significant decreased in the mean ulcer index along with  LTD4 concentration, LTB4 concentration .  These results suggest that the leukotrienes play an important role in  acetyl salicylic acid induced gastric ulcerations and gastroprotective activity of montelukast can be attributed to decreased activity of leukotrienes in gastric mucosa . Keywords :  Gastric ulcer , H.pylori , Non-steroidal anti-inflammatory drugs , montelukas

Storage Reduction of Mujeb Dam Reservoir in Jordan due to Sedimentation

The flow of water from the watershed upstream of a reservoir is capable of eroding the drainage area and of depositing material either upstream of the reservoir or in the still water of the reservoir causing reservoir sedimentation. The impact of reservoir sedimentation is reducing the storage capacity, decreasing ability to produce hydroelectric power and shortening of the life of the reservoir. In the present work, Al-Mujeb dam has been selected to estimate the quantity of sediment that reaches its reservoir using the modified universal soil loss model (MUSLE). Calibration and verification were carried out using measured data for volumes of runoff and cumulative sediment yields obtained from Eco-Sounder device. The quantities of sediment yield have been predicted for the next decade, when the reservoir storage capacity will be reduced by 23%. Strategies are recommended to update the Eco-Sounder measurements then the prediction process for another decade of time, and to reduce the soil erosion and minimize the sedimentation in the reservoir. Keywords: Sedimentation, Yield, Dams, Reservoir, Erosion, Soil Loss, Storage, Jordan. DOI: 10.7176/JEES/10-6-10 Publication date:June 30th 202

2 point block backward difference method for solving Riccati type differential problems

A two point block backward difference method is established to solve Riccati differential equations directly. Based on a predictor-corrector two point block backward difference method (2PBBD), a code is developed using a set of integration coefficients that eliminates the need to be calculated at every step change. The method requires calculating the integration coefficients only once in the beginning. The 2PBBD has an added advantage of a recurrence relationship between coefficients of different orders which provides a more elegant algorithm. The recurrence relationship between coefficients also reduces the computational cost

Solving Nonstiff Higher-Order Ordinary Differential Equations Using 2-Point Block Method Directly

We describe the development of a 2-point block backward difference method (2PBBD) for solving system of nonstiff higher-order ordinary differential equations (ODEs) directly. The method computes the approximate solutions at two points simultaneously within an equidistant block. The integration coefficients that are used in the method are obtained only once at the start of the integration. Numerical results are presented to compare the performances of the method developed with 1-point backward difference method (1PBD) and 2-point block divided difference method (2PBDD). The result indicated that, for finer step sizes, this method performs better than the other two methods, that is, 1PBD and 2PBDD

A review on the heat and mass transfer phenomena in nanofluid coolants with special focus on automotive applications

Engineered suspensions of nanosized particles (nanofluids) are characterized by superior thermal properties. Due to the increasing need for ultrahigh performance cooling in many industries, nanofluids have been widely investigated as next-generation coolants. However, the multiscale nature of nanofluids implies nontrivial relations between their design characteristics and the resulting thermo-physical properties, which are far from being fully understood. This pronounced sensitivity is the main reason for some contradictory results among both experimental evidence and theoretical considerations presented in the literature. In this Review, the role of fundamental heat and mass transfer mechanisms governing thermo-physical properties of nanofluids is assessed, from both experimental and theoretical point of view. Starting from the characteristic nanoscale transport phenomena occurring at the particle-fluid interface, a comprehensive review of the influence of geometrical (particle shape, size and volume concentration), physical (temperature) and chemical (particle material, pH and surfactant concentration in the base fluid) parameters on the nanofluid properties was carried out. Particular focus was devoted to highlight the advantages of using nanofluids as coolants for automotive heat exchangers, and a number of design guidelines was suggested for balancing thermal conductivity and viscosity enhancement in nanofluids. This Review may contribute to a more rational design of the thermo-physical properties of particle suspensions, therefore easing the translation of nanofluid technology from small-scale research laboratories to large-scale industrial applications

Finite elements in incompressible viscous flow including heat transfer

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