scholarly journals Modeling and Simulation for Steady State and Transient Pipe Flow of Condensate Gas

10.5772/23621 ◽  
2011 ◽  
Author(s):  
Li Changjun ◽  
Jia Wenlong ◽  
Wu Xi
Keyword(s):  
Steady State ◽  
Modeling And Simulation ◽  
Pipe Flow ◽  
Transient Pipe Flow

Numerical and experimental investigation of transient pipe flow

1994 ◽  
Vol 32 (5) ◽  
pp. 689-706 ◽  
Author(s):  
Amgad S. Elansary ◽  
M. Hanif Chaudhry ◽  
Walter Silva
Keyword(s):  
Experimental Investigation ◽  
Pipe Flow ◽  
Transient Pipe Flow

A New Hydraulic and Thermal Steady-State Calculation Program for Multiphase Pipe Network

2018 ◽  
Author(s):  
Di Fan ◽  
Qi Kang ◽  
Ruochen Zhang ◽  
Jing Gong ◽  
Changchun Wu
Keyword(s):  
Steady State ◽  
Adjacency Matrix ◽  
Pipe Flow ◽  
Incidence Matrix ◽  
Thermal Calculation ◽  
Efficient Production ◽  
Outlet Temperature ◽  
Pipe Network ◽  
Equilibrium Calculation ◽  
Flow Vector

With the continuous development of offshore oil and gas resources, calculation software for multiphase flowing pipe network has become an important tool for the design and daily operation of multiphase flowing pipe network. Improved accuracy of hydraulic and thermal calculation is an engineering requirement for economic and efficient production. Therefore, a new program is developed for multiphase pipe network in this paper. This program contains a general data structure to describe the complex connection of a pipe network. The structure is based on the conception of the incidence matrix and the adjacency matrix in graph theory. Two processes, hydraulic equilibrium calculation and thermodynamic equilibrium calculation are successively taken in this program to gain the steady-state for a multiphase pipe network. For the hydraulic equilibrium calculation, applying flow equation to each pipe in the network gains a pipe flow vector. A nonlinear system of equations, which represent flow balance of each node, is obtained by multiplying the incidence matrix and the pipe flow vector. To solve these equations, the Newton-Raphson iterative algorithm is used and afterwards, the hydraulic parameters of the pipe network are obtained. For thermal equilibrium calculation, since all the temperature of source nodes is known, the key step is to find the solution order of other node temperature. The program obtains the order by transforming the adjacency matrix. Deng temperature drop formula is used to calculate the end temperature of each pipe. When a node has more than one inflow, an average temperature based on the heat capacity and mass flow is adopted after gaining each pipe’s outlet temperature. Combining hydraulic and thermal algorithms, a complete set of solution program for steady-state of multiphase pipe network is compiled. In the end, two cases are performed to check the accuracy of the program. In the first case, a pipe network is created by using the data collected from a condensate gas gathering network in the South China Sea. The result indicates that the program has a good agreement with the actual data. In the second case, the program is applied in a single-phase network and gains almost the same result calculated by PipePhase and PipeSim.

Modeling and Simulation of the Steady-State and Transient Performance of a Three-Way Pressure Reducing Valve

2016 ◽  
Vol 138 (3) ◽  
Author(s):  
Osama Gad
Keyword(s):  
Steady State ◽  
Modeling And Simulation ◽  
Hydraulic Control ◽  
Transient Performance ◽  
Modes Of Operation ◽  
Transient Change ◽  
Discharge Coefficients ◽  
Proposed Model ◽  
Mathematical Formulas ◽  
Velocity Changes

This paper deals with modeling and simulation of a class of three-way pressure reducing valves. The study aims to point out the peculiarities of function and operation of this class of valves in the steady-state and transient modes of operation. A comprehensive nonlinear mathematical model is deduced in order to predict the performance of the studied valve in both modes. The proposed model takes into consideration most nonlinearities of the studied valve. A computer simulation, based on the proposed model, is performed to predict the steady-state and transient performance. During the simulation study, it was found that nonlinearity occurs due to the following factors: the transient change in the valve operating pressures and the change in the throttling areas of the valve restrictions and their discharge coefficients. The transient change in the valve operating pressures causes nonlinear velocity changes of the fluid flow passing through the throttling areas of the valve restrictions. These throttling areas usually have nonlinear mathematical formulas. The discharge coefficients of these throttling areas are assumed constant independent of the flow rates, Reynolds number, and dimensions of these areas. However, these parameters affect the discharge coefficient in a complicated manner. The validity of the proposed model is assessed experimentally in the steady-state and transient modes of operation. The results show good agreement between simulation and experiment in both modes. The study shows that the geometry of the throttling orifice, which connects the upstream port to the downstream port, plays an important role in the studied valve steady-state and transient performance. This result implies the need for further investigation of the effect of the dimensions of the throttling orifices on the steady-state and transient performance of hydraulic control valves.

Sign in / Sign up

Export Citation Format

Share Document