Simulation of flow transients in liquid pipeline systems

Download
index.pdf
2007
Koç, Gencer
Show full item record
280
views
334
downloads
Transient flow is a situation where the pressure and flow rate in the pipeline rapidly changes with time. Flow transients are also known as surge and Waterhammer which originates from the hammering sound of the water in the taps or valves. In liquid pipelines, preliminary design parameters are chosen for steady state operations, but a transient check is always necessary. There are various types of transient flow situations such as valve closures, pump trips and flow oscillations. During a transient flow, pressure inside the pipe may increase or decrease in an unexpected way that cannot be foreseen by a steady state analysis. Flow transients should be considered by a complete procedure that simulates possible transient flow scenarios and by the obtained results, precautions should be taken. There are different computational methods that can be used to solve and simulate flow transients in computer environment. All computational methods utilize basic v flow equations which are continuity and momentum equations. These equations are nonlinear differential equations and some mathematical tools are necessary to make these equations linear. In this thesis a computer program is coded that utilizes “Method of Characteristics” which is a numerical method in solving partial differential equations. In pipeline hydraulics, two partial differential equations, continuity and momentum equations are solved together, in order to obtain the pressure and flow rate values in the pipeline, during transient flow. In this thesis, MATLAB 7.1 is used as the programming language and obtained code is converted to a C# language to be able to integrate the core of the program with a user friendly Graphical User Interface (GUI). The Computer program is verified for different scenarios with the available real pipeline data and results of various reputable agencies. The output of the computer program is the tabulated pressure and flow rate values according to time indexes and graphical representations of these values. There are also prompts for users warning about possible dangerous operation modes of the pipeline components.
Mechanical Engineering., Transients (Dynamics).
http://etd.lib.metu.edu.tr/upload/2/12609018/index.pdf
https://hdl.handle.net/11511/17404
Graduate School of Natural and Applied Sciences, Thesis

Suggestions

Theory of impurity induced lattice distortions in the normal phase of charge density wave systems
Turgut, Sadi (1994-05-01)
A phenomenological Ginzburg-Laundau theory is applied to the normal phase of one-dimensional charge-density-wave systems with a finite concentration of impurities. It is found that the interaction between the impurities and the highly polarizable electron gas leads to a strong and oscillatory impurityimpurity interaction, which in turn leads to ordered impurity arrangements and to sizeable periodic lattice distortions. The effect is very strongly dependent on the charge of the impurities, their concentratio...
State estimation of transient flow in gas pipelines by a Kalman filter-based estimator
Durgut, İsmail; Leblebicioğlu, Mehmet Kemal (2016-09-01)
In this study, real-time estimation of flow rate and pressure along natural gas pipelines under transient flow condition is aimed. The estimation of the internal states of gas pipelines is based on a recursive discrete data filtering algorithm called the discrete Kalman filter. The state space representation of the transient flow in gas pipelines, which is required for the filtering algorithm, is established by a discrete form of the nonlinear partial differential equations (PDE's) describing the characteri...
Analysis of single phase convective heat transfer in microchannels with variable thermal conductivity and variable viscosity
Gözükara, Arif Cem; Güvenç Yazıcıoğlu, Almıla; Department of Mechanical Engineering (2010)
In this study simultaneously developing single phase, laminar and incompressible flow in a micro gap between parallel plates is numerically analyzed by including the effect of variation in thermal conductivity and viscosity with temperature. Variable property solutions for continuity, momentum and energy equations are performed in a coupled manner, for air as a Newtonian fluid. In these analyses the rarefaction effect, which is important for the slip flow regime, is taken into account by imposing slip veloc...
Modeling of underground gas storage in a depleted gas field
Gumrah, F; Izgec, O; Gokcesu, U; Bağcı, Ali Suat (Informa UK Limited, 2005-07-15)
It is possible to predict the behavior of fluids in permeable and porous medium under different operating conditions by using reservoir models. Since geological data and reservoir properties can be defined most accurately by reservoir models, it has been accepted as a reliable prediction tool among reservoir engineers. In this study, a gas reservoir has been modeled with IMEX Module of CMG Reservoir Simulator. Rock properties, gas composition and certain production data were entered to the model as input da...
Computational modelling of free surface flow in intake structures using flow 3D software
Aybar, Akın; Aydın, İsmail; Department of Civil Engineering (2012)
Intakes are inlet structures where fluid is accelerated to a certain flow velocity to provide required amount of water into a hydraulic system. Intake size and geometry affects the formation of flow patterns, which can be influential for hydraulic performance of the whole system. An experimental study is conducted by measuring velocity field in the hydraulic model of the head pond of a hydropower plant to investigate vortex formation. Vortex strength based on potential flow theory is calculated from the mea...
Citation Formats
G. Koç, “Simulation of flow transients in liquid pipeline systems,” M.S. - Master of Science, Middle East Technical University, 2007.
METU IIS - Integrated Information Service open@metu.edu.tr