Numerical Simulation of Solid Particle Erosion in a 90 Degree Bend for Gas Flow

Author(s):  
Ri Zhang ◽  
Haixiao Liu

Solid particle erosion in piping systems is a serious concern of integrity management in the oil and gas production, which has been widely predicted by the numerical simulation method. In the present work, every step of the comprehensive procedure is verified when applied to predicting the bend erosion for gas flow, and improvements are made by comparing different computational models. Firstly, five turbulent models are implemented to model the flow field in a 90 degree bend for gas flow and examined by the static pressure and velocity profile measured in experiments. Secondly, the particle velocities calculated by fully coupling and one-way coupling are compared with experimental data. Finally, based on the knowledge of flow modeling and particle tracking, four classic erosion equations are introduced to calculate the penetration rates in a 90 degree bend. By comparing with the experimental data available in the literature, it indicates that the k–ε model is the most accurate and effective turbulent model for gas pipe flow; the fully coupling makes the simulation of particle motion closer to measured data; and the Grant and Tabakoff equation presents better performance than other equations.

Author(s):  
G. Haider ◽  
A. Asgharpour ◽  
J. Zhang ◽  
S. A. Shirazi

Abstract During production of oil and gas from wells, solid particles such as removed scales or sand may accompany petroleum fluids. These particles present in this multiphase flow can impact inner walls of transportation infrastructure (straight pipelines, elbows, T-junctions, flow meters, and reducers) multiple times. These repeated impacts degrades the inner walls of piping and as a result, reduce wall thickness occur. This is known as solid particle erosion, which is a complex phenomenon involving multiple contributing factors. Prediction of erosion rates and location of maximum erosion are crucial from both operations and safety perspective. Various mechanistic and empirical solid particle erosion models are available in literature for this purpose. The majority of these models require particle impact speed and impact angle to model erosion. Furthermore, due to complex geometric shapes of process equipment, these solid particles can impact and rebound from walls in a random manner with varying speeds and angles. Hence, this rebound characteristic is an important factor in solid particle erosion modeling which cannot be done in a deterministic sense. This challenge has not been addressed in literature satisfactorily. This study uses experimental data to model particle rebound characteristics stochastically. Experimental setup consists of a nozzle and specimen, which are aligned at different angles so particles impact the specimen at various angles. Information regarding particle impact velocities before and after the impacts are obtained through Particle Tracking Velocimetry (PTV) technique. Distributions of normal and tangential components of particle velocities were determined experimentally. Furthermore, spread or dispersion in these velocity components due to randomness is quantified. Finally, based on these experimental observations, a stochastic rebound model based on normal and tangential coefficients of restitutions is developed and Computational Fluid Dynamics (CFD) studies were conducted to validate this model. The model predictions are compared with experimental data for elbows in series. It is found that the rebound model has a great influence on erosion prediction of both first and second elbows especially where subsequent particle impacts are expected.


Author(s):  
Peyman Zahedi ◽  
Soroor Karimi ◽  
Marzieh Mahdavi ◽  
Brenton S. McLaury ◽  
Siamack A. Shirazi

Solid particle erosion has been recognized as a major concern in the oil and gas production industry. It has been observed that erosion can cause serious and costly damage to equipment and pipelines. Accordingly, different studies have been performed in order to investigate erosion caused by solid particles entrained in the flow. Both experimental and modeling approaches have been used in the past to analyze solid particle erosion under different conditions to be able to mitigate these problems. The goal of this paper is to use a Computational Fluid Dynamic (CFD) erosion model to predict erosion caused by particles flowing in 90 degree and long radius bends. The fluid flow model is coupled with a Lagrangian particle tracking approach. The CFD-based prediction procedure consists of three main steps: flow modeling, particle tracking and erosion calculation. The Reynolds Stress Model (RSM) is used as the turbulence model for all fluid flow simulations. Solid particles are injected from the inlet of the pipe and tracked throughout the bend. The effect of the number of particles released on the predicted maximum erosion magnitude has been investigated. In order to study the grid independency of the solution, erosion is predicted for 5 different grid spacings to accurately predict the flow and erosion rates. In order to assess the quality of the numerical predictions of the erosion rate, experimental data for single-phase (gas) flow with sand in a 3-inch pipe were used. The effects of particle size, fluid velocity, pipe diameter and radius as well as particle rebound model on erosion pattern and magnitude are also investigated. Comparison of these results with experimental erosion data demonstrates good agreement of the erosion trends. It is found that the location of highest erosion for single-phase (gas) flow at low pressure containing sand is around 45° in the elbow. It has been also observed that the 300 μm particles cause approximately two times higher metal loss compared to the 150 μm particles. This higher erosion magnitude is not only caused by the increase in particle momentum but also by the significant increase in particle sharpness for the 300 μm sand. Moreover, simulation results indicate that the increase in gas superficial velocity leads to an increase in the erosion magnitude. According to the results, erosion ratios were reduced exponentially with the increase in pipe diameter at constant flow conditions and particle properties. Furthermore, two available rebound models in the literature were investigated, and simulations illustrate that both methods are in reasonable agreement with experimental data.


2021 ◽  
pp. 79-120

Abstract This chapter covers common types of erosion, including droplet, slurry, cavitation, liquid impingement, gas flow, and solid particle erosion, and major types of wear, including abrasive, adhesive, lubricated, rolling, and impact wear. It also covers special cases such as galling, fretting, scuffing, and spalling and introduces the concepts of tribocorrosion and biotribology.


2009 ◽  
Vol 6 (1) ◽  
pp. 91-97 ◽  
Author(s):  
Guomei Li ◽  
Yueshe Wang ◽  
Renyang He ◽  
Xuewen Cao ◽  
Changzhi Lin ◽  
...  

2021 ◽  
Author(s):  
Yeshwanthraj Rajkumar ◽  
Soroor Karimi ◽  
Siamack A. Shirazi

Abstract The entrainment of solid particles within the produced fluids can cause solid particle erosion by impacting the piping of production and transportation facilities. Liquid dominated flows are commonly encountered in deep water subsea pipelines while producing oil and gas fluids. It is of great importance to predict the erosion pattern and magnitude for elbows in series in liquid-solid flows as in the oil and gas productions, liquids tends to produce more solid particles compared to gas-solid flows. In the current work, erosion of elbows in series for different particle sizes are investigated by using computational fluid dynamics (CFD) and compare the erosion pattern results with the results of paint removal experiments using a 76.2 mm diameter acrylic elbows, qualitatively. CFD simulations have been performed to study the particle size effects on erosion using Reynolds stress turbulence model (RSM) and Low-Reynolds number K-ε model. Grid refinement studies have been performed and particles are rebounded at the particle radius to accurately examine the effects of particle sizes on solid particle erosion of these elbows. The CFD results shows that significant erosion is observed at the inner wall of the first elbow for larger particles, and the maximum erosion can be seen towards the end of the second elbow for 300 μm particle size.


2014 ◽  
Vol 1065-1069 ◽  
pp. 1911-1915
Author(s):  
Bao Rui Xu ◽  
Ming Hu Jiang ◽  
Li Xin Zhao ◽  
Fang Tan ◽  
Xiao Guang Zhang

Elbow as common components in the gas pipeline fails easily to natural gas carrying solid particle erosion in the process of practical work. From the viewpoint of hydromechanics, the paper analyses the flow field distribution of manifold pressure and gas-solid trajectory by using the Gambit model and Fluent software in view of the right-angle elbow and numerical simulation of the adjacent manifold. The result obtains the situation about the manifold inner wall by the solid particle erosion wear. The simulation results show more intuitively the elbow, the most prone to erosion part in the manifold adjacent area and shape in erosion. Meanwhile, the paper analyses the factors affecting the occurrence and development of erosion.


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