Sharif Digital Repository

Multiphase flows are commonly encountered in oil and gas industries. Flow fields in production operations are often complex and include multiphase flows of gas and liquid. The prediction of pressure gradients, liquid holdup and flow patterns occurring during the simultaneous flow of gas and liquid in pipes and wellbores is necessary in designing production facilities. Previously, due to their complex nature, these flow patterns have been mostly investigated only experimentally and empirical correlations based on the experimental data. From another point of view, it is almost impossible to experimentally realize all the flowing conditions for each of the flowing patterns. Nowadays, computer... 

One of the common and frequent problems in sewer systems is sediment deposit in the pipes and conduits. In a sewer system, most of the pipes experience extensive fluctuations of flow rate during their operation. There could be high and low flows of fluids passing through the pipe. In the former, solid particles will pass through the pipe because of the high velocity of the flow, while in the latter, velocity of the flow is lower than the self cleaning velocity. Lower velocities of flow lead to deposition of solid particles inside the pipe. As a result, several problems such as decrease of pipe capacity, lower velocity and system over flow happen. A promising solution to overcome this problem... 

Nowadays, radical increase in energy consumption guides humankind to find and harvest some alternative energy resources. Between the energy resources that have ever been known, Solar Energy is the most traditional one and Solar Water Heaters (SWHs) are the most ancient tools that have been used to store this energy up to now. Regarding this issue, many researches have been done to investigate different aspects of SWHs and the most conventional type was Thermosyphon SWH system. In this study, our aim is to investigate the influence of Pulsating Heat Pipes (PHPs) application as a heat transfer tool to convey absorbed solar energy to hot water reservoir of a SWH. In order to do this research,... 

In the present study, design and manufacturing of a connected pipe liquid fuel ramjet test platform is implemented for performance investigation of a research liquid fuel ramjet burner in the thermodynamic flight conditions. Design and manufacturing of platform systems include: the hot air supply system, the liquid fuel system and the square cross-sectional combustion chamber with the v-gutter shape flame holder. In order to determine the performance range of subsystems, calibration process has been carried out. Calibration process of the hot air supply system includes: determining of the burner inlet velocity and temperature. Also, calibration of the liquid fuel system includes: determining... 

Regarding high importance of casing pipes in oil industry also considering that they have not been producing domestically (with specific features), the main object of this research is feasibility study of establishment of a casing pipe threading plant which produces such kind of pipes. Usage of Casing PipesIs defining as a separator between wall of oil well and its core. The operation starts with driving and fixing a casing pipe to the oil well to avoid its collapsing during excavation process , then next casing pipes will be driven to the well and will be fixed to the previous pipes. During current research, after gathering all related financial and technical data, evaluation of “Net... 

In small settling tanks, the sludges can be removed using perforated pipes. In this method the pipe is placed in the depth of a fluid and the lateral inflow through perforations lead to the outlet. Since there are few researches about hydraulic characteristic of perforated pipes, this research will investigate the hyadraulic characteristic of these pipes experimentally. One of the main objectives of these pipes is to use the entire lenghte of the pipe and also provide the uniform distribution of inflow. In the past studies, it was found out that inflow mostly comes through downstream perforations. The objective of this research is to find the distribution of discharge along the perporated... 

Recently pulsating heat pipe have been used efficiently for heat transfer appications especially for heat excretion. As the name speaks, a pulsating movement of the fluid exists in the device and the principal aim of this research is to utilize this potential mechanical work ability of this movement and convert it to electrical energy. In this system slug-plug pulsating movement paradigm has been used in a U-shape pipe for supplying electromagnetic energy generator. The magnet positioning between hot and cold sources is moved in a pulsating form by the fluid and therefore electrical force is induced in the form of pulsating voltage difference. Fluid current is modeled by governing equations... 

Pulsating heat pipe (PHP) is a type of wickless heat pipe that has a simple structure and an outstanding thermal performance. Nanofluid is a type of fluifid in which nanoparticles are dispersed in a base fluid and has a better thermal conductivity in comparison with its base fluid. In this article, the performance of a nanofluid PHP is investigated. In order to simultaneously investigate the thermal performance and flow regimes in the PHP, a one-turn copper PHP with a Pyrex glass attached to its adiabatic section was used. A one-turn Pyrex PHP was also used to fully visualize flow patterns in the PHP. Our results showed that the material that a PHP made of and temperature of working fluid... 

Understanding of how fluid flow through porous media has many application in industry like Water filters technology and Gravel dams. also it’s very important in oil industry in areas like oil tank engineering. For doing this important thing many peoples tried to find out how fluid flows through the porous media they already invented the various kind of models, .the model used in this thesise is called pipe flow model which people use this model before but what I did have a little difference I used random lattice which people did not paid attention to it so the result of this model will be more trustable and close to what happens in nature. The result of this simulation showed us that the...