Sharif Digital Repository

In the oil industry, after drilling an oil well and laying pipes, it is time for the hydraulic fracturing process. In the process of hydraulic fracturing, a fracture must be created in the casing pipe of the well. The reason for this is that the oil from the existing reservoir enters the well so that it can be extracted. The end of the well must be blocked to cause a fracture in the well body. The reason is that after creating a fracture in the casing pipe, proppant particles are pumped together with water inside the well to keep it open. For the proppant particles to be placed inside the cracks, it is necessary to create pressure in the fracture area. To create pressure in the fracture area... 

In the present work, numerical simulation of cross-flow microfiltration of non-alcoholic beer in a tubular membrane has been studied. Finite element analysis was used as a powerful tool for simulation. The feed stream, which flows mainly tangentially to the porous membrane surface, is modeled by the Navier-Stokes equations. Porous wall conditions are described by the Darcy equation that relates the pressure gradient within a flow stream to the flow rate through the permeable wall. A pilot-scale cross-flow membrane filter was developed to verify the model results. Ceramic tubular membranes were used in this study. The cross-flow velocity of the feed solution was controlled at the laminar... 

Plug-in hybrid electric vehicles (PHEVs) present environmental and energy security advantages versus conventional gasoline vehicles. In the near future, the number of PHEVs will likely grow significantly in the world. In spite of the aforementioned advantages, the connection of PHEVs to the power grid may create a series of new challenges for electric utilities. If PHEV penetration exceeds a certain amount it can endanger power system security. In this research, a new charging control scheme which includes both the customer and grid acquiescence is presented. Optimal charging algorithm is developed which minimizes the electrical charging payment of customers. The optimization problem in this... 

Bashti Bone Plug Technique (BBPT) is a novel implant-less surgical methodology for Anterior Cruciate Ligament (ACL) reconstruction. The technique uses the core bone plug belonging to the patient, cut during tunneling with hole saw drill bit, to fix the ends of the tendon graft. Results show that when fitting the bone plug in this method, a large strike is required for fixation which leads to breaking the bone plug and consequently reducing the effective length of the bone plug inside the tunnel during fixation. Therefore, it was decided to use the sheath which covers the bone plug to overcome said challenges since during fixation with the sheath, Due to the low friction coefficient in these... 

After primary and secondary recovery processes more than 50 percent of oil remains in reservoirs. Therefore for more recovery from these reservoirs, methods of enhanced oil recovery should be applied.In this paper the effect of nanoparticles of SiO2 in size of 14 nm, on wettability is investigated. Using this nanoparticle, the wettability of carbonate rock in reservoirs could be changed and alter from oil-wet or mix-wet to water-wet. To assess this, hydrophilic changes of sandstone core and carbonate core are studied using the contact angle test. The same test is done on the carbonate core saturated with brine and oil that had received injection with brine and nanoparticles of SiO2 with two... 

In this study, experimental results of Ahvaz produced water treatment obtained in ultrafiltration process using a polymeric membrane formed from Polyacrylonitrile (PAN) with 0.2 µm poreshave been reported. In this process the effects of different factors including transmembrane pressure (TMP), cross flow velocity (CFV) and feed temperature on permeate flux, membrane fouling resistance and TOC rejection was investigated. The results show that optimum conditionswere found in the range of TMP: 1.5-3 bar, CFV: 1-1.5 m/s and operating temperature 40°C.Results show that under optimum conditions the final permeate flux for produced water of Asmari outlet of Skimmer unit was 30 L/m2.h, and the...