The Experts below are selected from a list of 105942 Experts worldwide ranked by ideXlab platform
Afshin Ghanbarzadeh - One of the best experts on this subject based on the ideXlab platform.
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a state space model for Transient Flow simulation in natural gas pipelines
Journal of Natural Gas Science and Engineering, 2012Co-Authors: Rezvan Alamian, Morteza Behbahaninejad, Afshin GhanbarzadehAbstract:A Transient Flow simulation for gas pipelines and networks is proposed. The proposed Transient Flow simulation is based on the state space equations. These equations are derived by the transfer function equations. However, the transfer function model cannot be used for a complicated network. One can easily apply a state space model for a large and complicated network. For a state space model, the equivalent transfer functions of the nonlinear governing equations are derived for different boundary condition types. Next, the state space equations are derived from the transfer functions. To verify the accuracy of the proposed simulation, the results obtained are compared with those of the conventional finite difference schemes (such as total variation diminishing algorithms, method of lines, and other finite difference implicit and explicit schemes). The effect of the Flow inertia is incorporated in this simulation. The accuracy and computational efficiency of the proposed method are discussed for a single gas pipeline and a sample gas network; besides for accuracy of this method for different boundary conditions, results for a sample gas pipeline with different boundary conditions are compared.
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Transient Flow Simulation in Natural Gas Pipelines Using the State Space Model
ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis Volume 3, 2010Co-Authors: Morteza Behbahani-nejad, Afshin Ghanbarzadeh, Rezvan AlamianAbstract:A Transient Flow simulation for gas pipelines and networks is proposed. The proposed Transient Flow simulation is based on the state space equations. The equivalent transfer functions of the nonlinear governing equations are derived for different boundary conditions types. Next, the state space equations are derived from the transfer functions. To verify the accuracy of the proposed simulation, the results obtained are compared with those of the conventional finite difference schemes (such as total variation diminishing algorithms, method of lines, and other finite difference implicit and explicit schemes). The effect of the Flow inertia is incorporated in this simulation. The accuracy and computational efficiency of the proposed method are discussed for a single gas pipeline and a sample gas network.Copyright © 2010 by ASME
Rao S Govindaraju - One of the best experts on this subject based on the ideXlab platform.
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a semi analytical model for Transient Flow to a subsurface tile drain
Journal of Hydrology, 2006Co-Authors: Jennifer S Stillman, Nathan W Haws, Rao S GovindarajuAbstract:The goal of this paper is to develop and test a semi-analytical model for event-based Transient Flow to a subsurface tile drain. A sharp-front theory was used to describe redistribution of infiltrated water in the vadose zone. New approximate analytical solutions in terms of Fourier series were sought for the Boussinesq equation describing subsurface saturated Flow subject to time-dependent recharge. Both one and two-term solutions of the series approximation were compared with observed tile hydrograph data from the Purdue Water Quality Field Station (WQFS) in West Lafayette, Indiana. In general, the models were able to capture the peaks of the tile-drain hydrographs, as well as the times-to-peak and the times-of-initial-response to rainfall events. The models performed particularly well for rainfall events with single-burst hyetographs, and in the prediction of the first hydrograph peak from multiple-burst hyetographs, though subsequent peaks could not be captured as well. A further comparison of results from the one-term model with those from HYDRUS 2D suggested that the one-term model is adequate for estimating Transient Flow to a tile drain. The solution developed here holds promise for extension to larger watersheds where the hydrology is governed by tile drains.
Rezvan Alamian - One of the best experts on this subject based on the ideXlab platform.
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a state space model for Transient Flow simulation in natural gas pipelines
Journal of Natural Gas Science and Engineering, 2012Co-Authors: Rezvan Alamian, Morteza Behbahaninejad, Afshin GhanbarzadehAbstract:A Transient Flow simulation for gas pipelines and networks is proposed. The proposed Transient Flow simulation is based on the state space equations. These equations are derived by the transfer function equations. However, the transfer function model cannot be used for a complicated network. One can easily apply a state space model for a large and complicated network. For a state space model, the equivalent transfer functions of the nonlinear governing equations are derived for different boundary condition types. Next, the state space equations are derived from the transfer functions. To verify the accuracy of the proposed simulation, the results obtained are compared with those of the conventional finite difference schemes (such as total variation diminishing algorithms, method of lines, and other finite difference implicit and explicit schemes). The effect of the Flow inertia is incorporated in this simulation. The accuracy and computational efficiency of the proposed method are discussed for a single gas pipeline and a sample gas network; besides for accuracy of this method for different boundary conditions, results for a sample gas pipeline with different boundary conditions are compared.
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Transient Flow Simulation in Natural Gas Pipelines Using the State Space Model
ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis Volume 3, 2010Co-Authors: Morteza Behbahani-nejad, Afshin Ghanbarzadeh, Rezvan AlamianAbstract:A Transient Flow simulation for gas pipelines and networks is proposed. The proposed Transient Flow simulation is based on the state space equations. The equivalent transfer functions of the nonlinear governing equations are derived for different boundary conditions types. Next, the state space equations are derived from the transfer functions. To verify the accuracy of the proposed simulation, the results obtained are compared with those of the conventional finite difference schemes (such as total variation diminishing algorithms, method of lines, and other finite difference implicit and explicit schemes). The effect of the Flow inertia is incorporated in this simulation. The accuracy and computational efficiency of the proposed method are discussed for a single gas pipeline and a sample gas network.Copyright © 2010 by ASME
Jennifer S Stillman - One of the best experts on this subject based on the ideXlab platform.
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a semi analytical model for Transient Flow to a subsurface tile drain
Journal of Hydrology, 2006Co-Authors: Jennifer S Stillman, Nathan W Haws, Rao S GovindarajuAbstract:The goal of this paper is to develop and test a semi-analytical model for event-based Transient Flow to a subsurface tile drain. A sharp-front theory was used to describe redistribution of infiltrated water in the vadose zone. New approximate analytical solutions in terms of Fourier series were sought for the Boussinesq equation describing subsurface saturated Flow subject to time-dependent recharge. Both one and two-term solutions of the series approximation were compared with observed tile hydrograph data from the Purdue Water Quality Field Station (WQFS) in West Lafayette, Indiana. In general, the models were able to capture the peaks of the tile-drain hydrographs, as well as the times-to-peak and the times-of-initial-response to rainfall events. The models performed particularly well for rainfall events with single-burst hyetographs, and in the prediction of the first hydrograph peak from multiple-burst hyetographs, though subsequent peaks could not be captured as well. A further comparison of results from the one-term model with those from HYDRUS 2D suggested that the one-term model is adequate for estimating Transient Flow to a tile drain. The solution developed here holds promise for extension to larger watersheds where the hydrology is governed by tile drains.
Huan-feng Duan - One of the best experts on this subject based on the ideXlab platform.
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Transient Flow of liquid in plastic pipes
Strojniski Vestnik-journal of Mechanical Engineering, 2020Co-Authors: Kamil Urbanowicz, Huan-feng Duan, Anton BergantAbstract:Nowadays, plastic pipes play a key role in fluid conveyance, for example, in urban water supply systems. Dynamic analysis of designed water pipe networks requires the use of numerical methods that allow for solving basic equations that describe Transient Flows occurring in plastic pipes. In this paper, the main equations were formulated with pressure (p) and velocity (v) as the principal variables. A novel simplified retarded strain solution is used to properly model the pipe-wall viscoelasticity effect during Transient Flow process. Unsteady friction is calculated with the use of a filtered weighting function (with three exponential terms). The proposed numerical method enables the efficient modelling of Transient Flow in plastic pressurized pipes. Extensive simulations are performed and compared with experimental results known from three different European research centres (London, Cassino, and Lyon), with the aim of demonstrating the impacts of plastic pipe properties and frequency-dependent hydraulic resistance on Transient pipe Flow oscillations. The effectiveness of the proposed method for determining the creep functions of plastic pipes is also examined and discussed.
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uncertainty analysis of Transient Flow modeling and Transient based leak detection in elastic water pipeline systems
Water Resources Management, 2015Co-Authors: Huan-feng DuanAbstract:In the Transient Flow modeling and analysis of practical water pipeline systems, discrepancies commonly exist between numerical simulation results and experimental measurement data. Such discrepancies are usually accounted for the inaccuracy and inadequacy of the used mathematical models and/or the lack of understanding of the hydrodynamic physics for Transient pipe Flows in the literature. However, the variability or uncertainty of the parameters for such numerical model inputs may also attribute to these discrepancies, especially in complex pipeline systems. This paper investigates the effects of different system uncertainties on the Transient Flow modeling and analysis such as pipe system design and leak detection. Different factors of pipe and fluid properties as well as system operations and complexities are considered for the uncertainty analysis. The one-dimensional (1D) water hammer model and the Monte-Carlo simulation (MCS) method are used in this investigation. The analysis results in this study demonstrate that the variability of the Transient Flow modeling can be easily affected by the uncertainty factors of wave speed and system complexities, while the Transient-based leak detection is more sensitive to the uncertainty factors of wave speed and data measurement than the factors of valve operation and initial hydraulic condition.
