Cryogenic pipe flow simulation for liquid nitrogen with vacuum insulated pipe (VIP) and Polyurethane (PU) foam insulation under steady-state conditions

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.

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Integral methods of calculation of heat transfer and drag under conditions of turbulent pipe flow of liquid of variable properties: Steady-state and quasi-steady-state flows in a round pipe with constant density of heat flux to the wall

High Temperature ◽

10.1134/s0018151x07010075 ◽

2007 ◽

Vol 45 (1) ◽

pp. 49-57 ◽

Cited By ~ 1

Author(s):

E. P. Valueva

Keyword(s):

Heat Transfer ◽

Heat Flux ◽

Steady State ◽

Pipe Flow ◽

Turbulent Pipe Flow ◽

Constant Density ◽

Quasi Steady State ◽

Variable Properties ◽

Integral Methods ◽

Methods Of Calculation

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Fluid Transmission Line Modeling Using a Variational Method

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.482449 ◽

1998 ◽

Vol 122 (1) ◽

pp. 153-162 ◽

Cited By ~ 33

Author(s):

Jari Ma¨kinen ◽

Robert Piche´ ◽

Asko Ellman

Keyword(s):

Differential Equations ◽

Variational Method ◽

Ordinary Differential Equations ◽

Transmission Lines ◽

Pipe Flow ◽

Transient Flow ◽

Numerical Models ◽

Flow Simulation ◽

Gibbs Phenomenon ◽

Turbulent Pipe Flow

A variational method is used to derive numerical models for transient flow simulation in fluid transmission lines. These are generalizations of models derived using the more traditional modal method. Three different transient compressible laminar pipe flow models are considered (inviscous, one-dimensional linear viscous, and two-dimensional dissipative viscous flow), and a model for transient turbulent pipe flow is given. The (model) equations in the laminar case are given in the form of a set of constant coefficient ordinary differential equations, and for the turbulent case (model) in the form of a set of nonlinear ordinary differential equations. Explicit equations are given for various end conditions. Attenuation factors, similar to the window functions used in spectral analysis, are used to attenuate Gibbs phenomenon oscillations. [S0022-0434(00)03201-9]

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Predictions of Flow Separation at the Valve-Seat for Steady-State Port-Flow Simulation

Volume 2: Instrumentation, Controls, and Hybrids; Numerical Simulation; Engine Design and Mechanical Development; Keynote Papers ◽

10.1115/icef2014-5667 ◽

2014 ◽

Cited By ~ 1

Author(s):

Tao Fang ◽

Satbir Singh

Keyword(s):

Steady State ◽

Mass Flow Rate ◽

Mass Flow ◽

Flow Rate ◽

Flow Separation ◽

Combustion Engine ◽

Flow Simulation ◽

Valve Lift ◽

Valve Seat ◽

Mesh Density

Steady-state port-flow simulations with static valve lift are often utilized to optimize the performance of intake system of an internal combustion engine. Generally, increase in valve lift results in higher mass flow rate through the valve. But in certain cases, mass flow rate can actually decrease with increased valve lift, caused by separation of turbulent flow at the valve-seat. Prediction of this phenomenon using computational fluid dynamics (CFD) models is not trivial. It is found that the computational mesh significantly influences the simulation results. A series of steady-state port flow simulation are carried out using a commercial CFD code. Several mesh topologies are applied for the simulations. The predicted results are compared with available experimental data from flow bench measurements. It is found that the flow separation and reduction in mass flow rate with increased valve lift can be predicted when high mesh density is used in the proximity of the valve seat and the walls of the intake port. Higher mesh density also gives better predictions of mass flow rate compared to the experiments, but only for high valve lifts. For low valve lifts, the error in predicted flow rate is close to 13%.

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Pipe flow simulation software: A team approach to solve an engineering education problem

Journal of Computing in Higher Education ◽

10.1007/bf02948594 ◽

1996 ◽

Vol 7 (2) ◽

pp. 65-77

Author(s):

Renata S. Engel ◽

Morris A. Weinstock ◽

John P. Campbell ◽

Dhushy Sathianathan

Keyword(s):

Engineering Education ◽

Pipe Flow ◽

Flow Simulation ◽

Simulation Software ◽

Team Approach

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Optimum geometry of parabolic trough collectors with optical and thermal criteria

International Review of Applied Sciences and Engineering ◽

10.1556/1848.2017.8.1.7 ◽

2017 ◽

Vol 8 (1) ◽

pp. 45-50 ◽

Cited By ~ 2

Author(s):

S. Pavlovic ◽

E. Bellos ◽

V. Stefanovic ◽

C. Tzivanidis

Keyword(s):

Steady State ◽

Optimum Design ◽

Thermal Performance ◽

Focal Length ◽

Flow Simulation ◽

Inlet Temperature ◽

Exergetic Efficiency ◽

Parabolic Trough ◽

Optimum Geometry ◽

The Impact

The objective of this work is to investigate the impact of the geometric dimensions of parabolic trough collector (PTC) in the optical, energetic and exergetic efficiency. The module of the commercial LS-3 PTC is examined with SOLIDWORKS FLOW SIMULATION in steady-state conditions. Various combinations of reflector widths and receiver diameters are tested. The optical and the thermal performance, as well as the exergetic performance are calculated for all the examined configurations. According to the final results, higher widths demands higher receiver diameter for optimum performance. For inlet temperature equal to 200 °C, the optimum design was find to be 3000 mm width with 42.5 mm receiver diameter, with the focal length to be 1840 mm (this is kept constant in all the cases). The results of this work and the presented methodology can be used as guidelines for the design of optimum PTC in the future.

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