scholarly journals Low Pressure Experimental Validation of Low-Dimensional Analytical Model for Air–Water Two-Phase Transient Flow in Horizontal Pipelines

Fluids ◽  
2021 ◽  
Vol 6 (6) ◽  
pp. 220
Author(s):  
Hamdi Mnasri ◽  
Amine Meziou ◽  
Matthew A. Franchek ◽  
Wai Lam Loh ◽  
Thiam Teik Wan ◽  
...  
Keyword(s):  
Multiphase Flow ◽  
Experimental Validation ◽  
Flow Model ◽  
Transient Flow ◽  
Volume Fraction ◽  
Laboratory Data ◽  
Low Pressure ◽  
Two Phase ◽  
Fluid Properties ◽  
Low Dimensional

This paper presents a low-pressure experimental validation of a two-phase transient pipeline flow model. Measured pressure and flow rate data are collected for slug and froth flow patterns at the low pressure of 6 bar at the National University of Singapore Multiphase Flow Loop facility. The analyzed low-dimensional model proposed in comprises a steady-state multiphase flow model in series with a linear dynamic model capturing the flow transients. The model is based on a dissipative distributed parameter model for transient flow in transmission lines employing equivalent fluid properties. These parameters are based solely on the flowing conditions, fluid properties and pipeline geometry. OLGA simulations are employed as an independent method to validate the low-dimension model. Both low-dimensional and OLGA models are evaluated based on the estimated two-phase pressure transients for varying gas volume fraction (GVF). Both models estimated the two-phase flow transient pressure within 5% mean absolute percent error of the laboratory data. Additionally, an unavoidable presence of entrained air within a pipeline is confirmed for the case of 0% GVF as evidenced by the pressure transient estimation. Thus, dampened oscillations in the simulated 0% GVF case exists owing to an increase in the fluid compressibility.

A ONE-DIMENSIONAL TWO-PHASE FLOW MODEL AND EXPERIMENTAL VALIDATION FOR A FLASHING VISCOUS LIQUID IN A SPLASH PLATE NOZZLE

2015 ◽  
Vol 25 (9) ◽  
pp. 795-817 ◽  
Author(s):  
Mika P. Jarvinen ◽  
A. E. P. Kankkunen ◽  
R. Virtanen ◽  
P. H. Miikkulainen ◽  
V. P. Heikkila
Keyword(s):  
Viscous Liquid ◽  
Experimental Validation ◽  
Flow Model ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Two Phase ◽  
One Dimensional

scholarly journals A relaxation scheme for a hyperbolic multiphase flow model

2019 ◽  
Vol 53 (5) ◽  
pp. 1763-1795 ◽  
Author(s):  
Khaled Saleh
Keyword(s):  
Multiphase Flow ◽  
Flow Model ◽  
Two Phase Flow ◽  
Equations Of State ◽  
Energy Inequality ◽  
Approximation Error ◽  
Finite Volume Scheme ◽  
Phase Flow ◽  
Two Phase ◽  
Relaxation Scheme

This article is the first of two in which we develop a relaxation finite volume scheme for the convective part of the multiphase flow models introduced in the series of papers (Hérard, C.R. Math. 354 (2016) 954–959; Hérard, Math. Comput. Modell. 45 (2007) 732–755; Boukili and Hérard, ESAIM: M2AN 53 (2019) 1031–1059). In the present article we focus on barotropic flows where in each phase the pressure is a given function of the density. The case of general equations of state will be the purpose of the second article. We show how it is possible to extend the relaxation scheme designed in Coquel et al. (ESAIM: M2AN 48 (2013) 165–206) for the barotropic Baer–Nunziato two phase flow model to the multiphase flow model with N – where N is arbitrarily large – phases. The obtained scheme inherits the main properties of the relaxation scheme designed for the Baer–Nunziato two phase flow model. It applies to general barotropic equations of state. It is able to cope with arbitrarily small values of the statistical phase fractions. The approximated phase fractions and phase densities are proven to remain positive and a fully discrete energy inequality is also proven under a classical CFL condition. For N = 3, the relaxation scheme is compared with Rusanov’s scheme, which is the only numerical scheme presently available for the three phase flow model (see Boukili and Hérard, ESAIM: M2AN 53 (2019) 1031–1059). For the same level of refinement, the relaxation scheme is shown to be much more accurate than Rusanov’s scheme, and for a given level of approximation error, the relaxation scheme is shown to perform much better in terms of computational cost than Rusanov’s scheme. Moreover, contrary to Rusanov’s scheme which develops strong oscillations when approximating vanishing phase solutions, the numerical results show that the relaxation scheme remains stable in such regimes.

Nanoparticles-Laden Gas Film in Aerostatic Thrust Bearing

2014 ◽  
Vol 136 (3) ◽  
Author(s):  
Zhiru Yang ◽  
Dongfeng Diao ◽  
Xue Fan ◽  
Hongyan Fan
Keyword(s):  
Effective Viscosity ◽  
Flow Model ◽  
Thrust Bearing ◽  
Volume Fraction ◽  
Load Capacity ◽  
Sio2 Nanoparticles ◽  
Enhancement Effect ◽  
The Novel ◽  
Two Phase ◽  
Air Film

Nanoparticles-laden gas film (NLGF) was formed by adding SiO2 nanoparticles with volume fraction in the range of 0.014–0.330% and size of 30 nm into the air gas film in a thrust bearing. An effective viscosity of the gas-solid two phase lubrication media was introduced. The pressure distribution in NLGF and the load capacity of the thrust bearing were calculated by using the gas-solid two phase flow model with the effective viscosity under the film thicknesses range of 15–60 μm condition. The results showed that the NLGF can increase the load capacity when the film thickness is larger than 30 μm. The mechanism of the enhancement effect of load capacity was attributed to the increase of the effective viscosity of the NLGF from the pure air film, and the novel lubrication media of the NLGF can be expected for the bearing industry application.

Automated Subsea Architecture Optimization Using Low-Dimensional Multiphase Flow Models

2019 ◽  
Author(s):  
Zurwa Khan ◽  
Amine Meziou ◽  
Reza Tafreshi ◽  
Matthew Franchek ◽  
Karolos Grigoriadis
Keyword(s):  
Multiphase Flow ◽  
Thermal Model ◽  
Effective Control ◽  
Two Phase ◽  
Validation Data ◽  
Flow Models ◽  
Dimensional Models ◽  
Low Dimensional ◽  
Architecture Optimization

Abstract Due to the global increase in energy demand, the need for economic oil and gas production is rising more than ever. Therefore, it is necessary to ensure that subsea architecture designs are economical and safety oriented. While numerous challenges are encountered during subsea system’s installation and operation phases, most of these challenges can be avoided by ensuring an economical and reliable design. For a safe and cost-effective design and operating scenario, it is essential to predict the hydraulic and thermal behavior of multiphase fluid encountered in petroleum pipelines for a range of conditions. This cannot be accomplished by empirical models, which are dependent on limited data available. Consequently, mechanistic low-dimensional models have been used for two-phase gas-liquid steady-state flow. However, mechanistic low-dimensional models assume adiabatic conditions, which is rarely the case in subsea architectures, which encounter cold surroundings. Therefore, to predict the temperature-based characteristics of multiphase flow in environments with thermal gradients, a thermal model has been developed and validated with experimental data. 80% of the validation data was predicted by this developed thermal model with error difference of less than 30%. The developed two-phase gasliquid thermal model was merged with Beggs and Brill hydraulic multiphase flow model to predict the overall behavior of two-phase gas-liquid flow, and used to develop an optimal model-based multi-well subsea architecture design. A case study of a four-well subsea system was used to demonstrate the automated subsea architecture optimization technique. Through this case study, it was shown that approximately 23% of savings in pipelines procurement could be made relative to the conventional designing approach. Industry standards, safety factors, and multiphase flow models were used to design jumpers and place the manifold for a subsea multi-well system. Merging hydraulic and thermal multiphase flow models showed the effect of temperature on the flow, which led to an optimized design for the subsea insulation in which issues such as wax deposition can be prevented. The resulting optimized subsea architecture was then implemented in Simscape® environment to obtain the transient response. Along with optimized subsea architecture automated design, the developed thermal model has the potential to be used for real-time prediction of two-phase flow rate, pressure drop and void fraction as virtual sensors to provide economical alternative to expensive and impractical hardware sensors. Furthermore, the developed model can also be used to design effective control strategies for multiphase flow regulation in jumpers and prevention of backflow at the manifold.

The Numerical Simulation of the Water Jet in Hydroentanglement

2011 ◽  
Vol 189-193 ◽  
pp. 2181-2184
Author(s):  
Heng Zhang ◽  
Xiao Ming Qian ◽  
Zhi Min Lu ◽  
Yuan Bai
Keyword(s):  
Numerical Simulation ◽  
Numerical Model ◽  
Multiphase Flow ◽  
Flow Model ◽  
Two Phase Flow ◽  
Water Jet ◽  
Phase Flow ◽  
Governing Equations ◽  
Two Phase ◽  
Set Up

The functions of hydroentangled nonwovens are determined by the degree of the fiber entanglement, which depend mainly on parameters of the water jet. According to the spun lacing technology, this paper set up the numerical model based on the simplified water jetting model, establishing the governing equations, and the blended two-phase flow as the multiphase flow model. This paper simulation the water needle after the water jetting from the water needle plate in the different pressure (100bar, 60bar, 45bar, 35bar).

Low-Dimensional Modeling of Transient Two-Phase Flow in Pipelines

2016 ◽  
Vol 138 (10) ◽  
Author(s):  
Amine Meziou ◽  
Majdi Chaari ◽  
Matthew Franchek ◽  
Rafik Borji ◽  
Karolos Grigoriadis ◽  
...  
Keyword(s):  
Steady State ◽  
Multiphase Flow ◽  
Transmission Line ◽  
Transmission Lines ◽  
Mechanistic Model ◽  
Phase Flow ◽  
Liquid Holdup ◽  
Two Phase ◽  
Low Dimensional ◽  
State Pressure

Presented are reduced-order models of one-dimensional transient two-phase gas–liquid flow in pipelines. The proposed model is comprised of a steady-state multiphase flow mechanistic model in series with a transient single-phase flow model in transmission lines. The steady-state model used in our formulation is a multiphase flow mechanistic model. This model captures the steady-state pressure drop and liquid holdup estimation for all pipe inclinations. Our implementation of this model will be validated against the Stanford University multiphase flow database. The transient portion of our model is based on a transmission line modal model. The model parameters are realized by developing equivalent fluid properties that are a function of the steady-state pressure gradient and liquid holdup identified through the mechanistic model. The model ability to reproduce the dynamics of multiphase flow in pipes is evaluated upon comparison to olga, a commercial multiphase flow dynamic code, using different gas volume fractions (GVF). The two models show a good agreement of the steady-state response and the frequency of oscillation indicating a similar estimation of the transmission line natural frequency. However, they present a discrepancy in the overshoot values and the settling time due to a difference in the calculated damping ratio. The utility of the developed low-dimensional model is the reduced computational burden of estimating transient multiphase flow in transmission lines, thereby enabling real-time estimation of pressure and flow rate.

Analysis of flow field in Si3N4 dry granulation chamber with non-standard composite structure

2020 ◽  
pp. 1-12
Author(s):  
Zhuting Jiang ◽  
Xiang Ning ◽  
Tao Duan ◽  
Nanxing Wu ◽  
Dongling Yu
Keyword(s):  
Flow Field ◽  
Composite Structures ◽  
Flow Model ◽  
Volume Fraction ◽  
Volume Distribution ◽  
Phase Flow ◽  
Two Phase ◽  
Dry Granulation ◽  
Combined Structure ◽  
Internal Distribution

In order to improve the whirling phenomenon of Si3N4 particles in the granulation chamber, the influence of the structure of the granulation chamber on the internal distribution is explored. Euler Euler’s two-phase flow model is established. The flow field in the combined structure granulation chamber with different layout is simulated. The volume distribution and velocity field change of Si3N4 particles in the combined structure granulation chamber with different layout are analyzed. The results show that the angle between two adjacent composite structures is 20∘, 60∘, 80∘ and completely standard the Si3N4 particles with volume fraction index greater than 0.8 account for 10.2%, 11.5%, 12.5% and 6.7% of the total volume respectively. When the combined structure is completely standard, several small convolutions are found. The whirling phenomenon in the granulation chamber is improved. When the angle between two adjacent composite structures is 20∘, 60∘, 80∘ and complete standard, the proportion of qualified particles is 59%, 64%, 66% and 68%. The fluidity index is 84, 85, 87 and 88, respectively. To sum up, the combination structure of the granulation chamber is a complete standard, it is beneficial to improve the spin phenomenon of Si3N4 particles in the granulation chamber.

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