Sharif Digital Repository

Because of a lot of water, gas and polymer injection processes in industry, two phase flow simulation is very useful. So performing experimental work to find out fluid flow behavior in a small scale of reservoir has special importance. The results in various scales will differ because of heterogeneity and different dominant flow regimes. To see this effects, comparison of two small scales, namely core and micromodel scales, has been studied using the scale up methods. In literature review, the scale up procedure, relative permeability methods and dimensionless numbers in two phase flows has been described. Here the relative permeability and oil... 

Gas injection processes are considered as the second largest Enhanced Oil Recovery processes after thermal processes. In Dealing with the problems of Continuous Gas Injection (CGI) processes, the substitute method of Water Alternating Gas (WAG) is gaining ever increasing attention in field applications. The Hybrid method has the advantages both CGI and WAG processes. Laboratory studies of gas injection methods to show the optimum method and the effect of pressure on the performance of this method is the main objective of this project. Results obtained from these tests can be used in the Enhanced Oil Recovery scenarios for this reservoir. In this project, experiments for Continuous Gas... 

Geomechanics has an immense impact on petroleum engineering and applies to the most aspects of petroleum extraction, from exploration and drilling to production and even reservoir abandonment. Studying the mechanical behavior of rocks in hydrocarbon reservoirs and overburden layers will lead to better characterization of mechanical state of the environment. Therefore, a solid understanding of rock mechanical behavior can play a crucial role in reducing operational issues of oil and gas extraction in different phases and prevent extra cost and time consumption. To illustrate, studies of wellbore stability and integrity, casing burst and collapse, drilling optimization, sand production,... 

Increasing the power of a turbocharged diesel engine without changing main engine components is important in industrial applications, with economic benefits. The engine power can be increased by higher boost pressure. In this research, the turbocharged diesel engine performance improvement was investigated to increase the engine power. As a case study, the performance improvement of OM355A turbocharged diesel engine carried out. For this purpose, the engine was modeled in boost module of the AVL software. First, naturally aspirated OM355 and turbocharged OM355A diesel engines were modeled. Then the simulation results were evaluated in compare with engine tests data. Maximum difference in... 

Pulsating heat pipe (PHP) is a two-phase device for the means of transferring high heat fluxes and is used extensively for the electronic cooling. In this study the different flow regimes in PHP with different fluids have been investigated. In this research, 3 different fluids including: Pure fluids, Ferro-fluid and surfactant solution with %50 filling ratio have been used. For ferro-fluid, 5 different concentrations and 3 type of magnetic fields have been operated in 2 different heat pipes. Results show that ferrofluid is more stable in Pyrex made-heat pipe for long period of time and no magnet mode has the best thermal performance due to high conductivity of fluid. In copper made-heat pipe... 

Modeling and Control are fundamental issues for fish robots, which can play basic roles in design, optimization, fabrication, and eventually utilization of them. A review on the literature reveals the shortage of an analytical closed form model with little simplifications and high precision, and also control works based on such models. Studying LAEBT theory, it is shown that this theory is suitable for determining the forces produced due to the tail movements considered in the present work, and then it is used to determine the forces. Experimental investigations by means of the setup made for this purpose showed that the obtained equations for the forces have got acceptable precision.... 

With regard to an increasing world population and the constant capacity of water resources, new and valid methods should be implemented to preserve freshwater resources and accordingly produce drinking water. In the present study, a solar hybrid system was studied by experimental and theoretical means to facilitate the transformation of waste heat from photovoltaic module (PV module) into useful heat that can be used in a solar desalination (SD) system for freshwater production purposes. The study aimed to fabricate a SD system by using both PV module and thermosyphon heat pipes (THPs) technologies in a single system. In the modeling section, the goal is to present a comprehensive model... 

Chemical flooding such as surfactant flooding in oil reservoirs can change the wettability and interfacial tension between oil and water and so reduce the residual oil saturation in the reservoir. Some of these materials can be adsorbed a lot on the surface of carbonate rocks, so it is difficult to predict the oil recovery factor in such process. Therefore it is necessary to survey the adsorption amount of surfactants in chemical EOR injections.In this thesis, the adsorption of a nonionic surfactant on the surface of carbonate rock is experimented and the proper model is obtained. Then the surfactant is injected in a core saturated with oil to observe the efficiency of this surfactant in... 

Drilling fluid is one the most important part of drilling operations in the oil and gas wells digging. From an economic point of view, almost 25 to 45% of drilling costs are allocated to drilling fluid. Drilling fluids consist of several components with different physical and structural forms which can be assumed as complex fluids. Optimum performance of the drilling process could be obtained through the dynamic fluid computation which requires a reliable mathematical model capable to predict transient-state and steady-state rheological behavior of drilling fluid. Generalized Newtonian models, such as the Bingham-plastic model, the power model, and the Herschel-Bulkley model, are the most... 

Today, the world energy crisis, the need to optimize its consumption and discussion to reduce fuel consumption has become a vital issue. The conventional vehicle air conditioning system due to compressor in refrigeration cycle, which has causes a severe loss in engine useful power, increasing fuel consumption, etc. Therefore, the main goal of this project is the feasibility of the vehicle cooler replacement with the vapor jet refrigeration cycle. In this cycle, the energy required for completing the refrigeration cycle is provided from the heat of the water inside the radiator that is possible with conventional refrigeration cycle. The first stage of this project includes design and... 

In present Thesis, the HDH desalination system has designed and fabricated based on three different functions. Two-stage bubble column humidification-dehumidification system, heat recovery converter, and the elimination of the cooling system are among the innovations of this study.Also, the desalination system is processed and controlled by a control system based on the Python language. The experiment is designed for three different systems based on the three different functions, different maximum temperatures and different mass ratios of water to air have been taken into account. Essential parameters of HDH systems have been analyzed in this study. The experimental results have pointed out... 

For several decades, turbocharging of internal combustion engines has been a wide spreading technology to increase the engine output power as much as possible. Turbocharger has two main components: compressor, and turbine. Therefore, increasing the efficiency of turbine and compressor has a major role in engine performance improvement. This has been a continuous research goal in 20th century. Considerable advances has been achieved until now. Turbocharger turbine should be matched to engine in a wide range operation conditions with high efficiency. Many researchers have published their achievements considering turbine elements design improvements. This research is focused on the turbine... 

During the last six decades, there were remarkable developments in the field of gas turbines. In the early 1950’s, the effciency of gas turbines was 20% and it is improved up to more than 40% for modern gas turbines. In addition, due to the implementation of the combined power cycles, the thermal effciency have been reached to 60%. According to the recent developments, further improvements in this field seem to be more costly and diffcult to obtain. Rotating detonation combustor (RDC) is a new generation of detonation combustors which has simpler design and several advantages compared to jet engine combustors, but it has its intrinsic problems which seem resolvable. Given that the RDC... 

Today, the world energy crisis, the need to optimize its consumption and discussion to reduce fuel consumption has become a vital issue. The conventional vehicle air conditioning system due to compressor in refrigeration cycle, which has causes a severe loss in engine useful power, increasing fuel consumption, etc. Therefore, the main goal of this project is the feasibility of the vehicle cooler replacement with the vapor jet refrigeration cycle. In this cycle, the energy required for completing the refrigeration cycle is provided from the heat of the water inside the radiator that is possible with conventional refrigeration cycle. The first stage of this project includes design and... 

Nowadays, the study of flow and heat transfer in turbine engines has become critical due to their increasing use and importance in various engineering industries. The critical issue of blade burning in the first row of turbine’s blades illuminates the critical roles of numerical and experimental activities in reducing these undesirable effects. Since blade cooling is directly related to the secondary air system, one important issue in blade burning research is to utilize the conjugate heat transfer approach. As Known, an increase of about 1% in the mass flow of air entering into the secondary air system would cause an increase of about 0.5% in the engine specific fuel consumption (SFC),... 

Gas turbine discs must be tested before they are installed in an engine for their mechanical properties and resistance to crack growth. Such test is usually done in a device called Spin Tester in which high rotational speed and temperature fluctuations can be applied to a disc. In this project a plug-in software is developed by which life of gas turbine discs under sever fluctuations of rotating speed and temperature can be assessed. The tests performed in the software are; stress analysis, fatigue analysis, crack initiation point, and finally 3-D fatigue crack growth path. The software is written using Python programming in ABAQUS. The software adds a sub-menu in ABAQUS Plugins as "Engine... 

Thermal management of electronics is a contemporary issue which is increasingly gaining importance in line with the advances in packaging technology. Immediate and consistent multi-disciplinary research is needed to cater to the prevailing trends of net power and flux levels of upcoming microelectronics products. Material science, packaging concepts, fabrication technology and novel cooling strategies are some of key areas requiring synchronal research for successful thermal management. Focusing on the latter area, this thesis attempts to describe the complex thermo-hydrodynamics of Closed Loop ... 

Electrohydrodynamic (EHD) printing is a novel approach for manufacturing high-resolution structures in micro and nanoscale. This technology is the promoted version of inkjet printing which has reduced nozzle clogging risk and improved the accessible resolution. In this method, ink droplets or jets are formed under the action of an electric field and are used as building blocks of the intended part or pattern. Most research in this field has focused on the formation of monolayer droplets and jets by this technology; however, the EHD printer has a great potential to produce core-shell microstructures in a controlled manner too. These microparticles have unique properties and applications due... 

Micropumps are regarded as one of the devices used in microsystems, which are responsible for pumping working fluid. The Mercury Magneto Reciprocating (MMR) micropump, which has been introduced for less than a decade, is an innovative kind of micropumps which the pumping agent includes three liquid metal droplets (LMD) placed inside lateral chambers and reciprocated by the electromagnetic force inside the chambers. The working fluid located inside the main channel is pumped through due to the movement of these three LMDs. The equations governing this micropump are complex and their numerical solution is a time-consuming process, due to electromagnetic, hydrodynamic, and unsteady effects. The... 

The problem of jet into a cross flow is one of the classic problems in fluid mechanics and has many engineering applications, such as in vector thrust control systems. Although many works have been done in this field, there have not been enough research in interactions of supersonic jets into compressible subsonic cross flows (specially its interaction with control surfaces downstream). Hence, the purpose of this research is to get better understanding of this interaction and its effects on control surfaces downstream (both numerical and experimental). Some of the individual achievements of this research are the design and manufacturing of supersonic jet system, parametric study of: boundary...