scholarly journals Study on the erosion wear in pipe fittings

2021 ◽  
Author(s):  
Manlai Zhang ◽  
◽  
Qin Zhang ◽  
Xiuwu Wang ◽  
Zhihong Zhou ◽  
...  
Keyword(s):  
Weight Loss ◽  
Erosion Rate ◽  
Surface Deformation ◽  
Dynamics Simulation ◽  
Pipeline System ◽  
Erosion Wear ◽  
Momentum Exchange ◽  
Two Phase ◽  
Dense Particle ◽  
Flow Equations

In the pipeline system for slurry, local erosion wear failure has become the main damage mechanism of pipe in the fracturing operations of oil-gas engineering. Computational Fluid Dynamics simulation is performed to determine the evolutionary process of erosion wear in tubing connector, which is the resistance of pipeline system, and a new way to predict the pipeline longevity is provided. Based on the Euler equation, solid particle concentration in the slurry and interphase momentum exchange are included in the liquid flow equations due to the influence of dense particle on slurry (slurry is a two-phase flow), and the particle trajectory were calculated in the Lagrange frame by analyzing the forces from the interaction of liquid and particle and particles impact. With the erosion damage model, the erosion rate/depth in the connector was calculated to reconstruct the mesh model of shoulder with 5 tori. Torus 1 is closest to axis while torus 5 is on the outmost wall of the connector. During the erosion event, greatest erosion and hence surface deformation occurs on tori 1 and 2, and this affects the surrounding flow and particle movement. After 10 hours of erosion, there was a dramatic drop in the maximum erosion rate, which illustrated a conservative prediction for pipeline service life if the initial erosion rate was used. An erosion experimental setup was also performed to identify the weight loss and erosion characteristic of the inner surface with erosion time of 55 hours. It was observed that the erosion simulations provided relative errors within 18% for erosion length and weight loss compared to the experimental values and a closed form equation for the erosion rate was proposed to predict the erosion life of tubing connector

Numerical Investigation of Sediment-Laden Flow in a High-Head Francis Turbine Runner

2013 ◽  
Vol 860-863 ◽  
pp. 1542-1546
Author(s):  
Hong Ming Zhang ◽  
Li Xiang Zhang
Keyword(s):  
Erosion Rate ◽  
Volume Fraction ◽  
Three Dimensional ◽  
Suction Side ◽  
Francis Turbine ◽  
Two Phase ◽  
Flow Equations ◽  
Maximum Value ◽  
Sand Erosion ◽  
Turbine Runner

The 3-D turbulent particulate-liquid two-phase flow equations are employed in this study. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the sand erosion rate on pressure side is more than on the suction side of the blade. The maximum value of sand volume fraction and the maximum value of sand erosion rate are at same location.

scholarly journals The erosion wear mechanism of liquid-solid two-phase high pressure manifold tee pipes

2021 ◽  
Vol 37 (1) ◽  
Author(s):  
H. Zhang ◽  
J. Zhang ◽  
L. Lv
Keyword(s):  
High Pressure ◽  
Shear Stress ◽  
Wall Shear Stress ◽  
Wear Mechanism ◽  
Erosion Rate ◽  
Fluid Velocity ◽  
Erosion Wear ◽  
Two Phase ◽  
Geometry Model ◽  
Wall Shear

The wall thickness of pressure pipe is often thinned due to the erosion wear, which leads to pipe failure and even safety accidents. In particular, the tee pipe is more prone to be erosive as a key component of transferring fluid with particles. Therefore, the erosion wear mechanism of high pressure manifold tee pipe based on liquid-solid two-phase flow is studied in this paper. Firstly, the standard tee pipe geometry model is established and the grid is divided. And then grid number independence is verified by the percentage difference. According to the structural characteristics of tee pipe, the wear of the inner wall under four different port combinations is predicted. In addition, the relationship between erosion rate and wall shear stress is further analyzed by fluid velocity, particle diameter and mass flow rate. Double tee pipes geometry model was established to explore the erosion wear on the inner walls. The effects of assembly length and different port combinations on erosion wear were discussed respectively. When the inlets are fixed, the wall shear stress distribution of the downstream tee pipe is mainly affected by the outlets. The assembly length mainly affects the erosion rate of the downstream tee pipe.

Determination of mechanical properties of two-phase and hybrid nanocomposites: experimental determination and multiscale modeling

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mahmoud Haghighi ◽  
Hossein Golestanian ◽  
Farshid Aghadavoudi
Keyword(s):  
Mechanical Properties ◽  
Ultimate Strength ◽  
Multiscale Modeling ◽  
Filler Content ◽  
Hybrid Nanocomposites ◽  
Dynamics Simulation ◽  
Strength Increase ◽  
Two Phase ◽  
Macro Scale ◽  
Elongation To Failure

Abstract In this paper, the effects of filler content and the use of hybrid nanofillers on agglomeration and nanocomposite mechanical properties such as elastic moduli, ultimate strength and elongation to failure are investigated experimentally. In addition, thermoset epoxy-based two-phase and hybrid nanocomposites are simulated using multiscale modeling techniques. First, molecular dynamics simulation is carried out at nanoscale considering the interphase. Next, finite element method and micromechanical modeling are used for micro and macro scale modeling of nanocomposites. Nanocomposite samples containing carbon nanotubes, graphene nanoplatelets, and hybrid nanofillers with different filler contents are prepared and are tested. Also, field emission scanning electron microscopy is used to take micrographs from samples’ fracture surfaces. The results indicate that in two-phase nanocomposites, elastic modulus and ultimate strength increase while nanocomposite elongation to failure decreases with reinforcement weight fraction. In addition, nanofiller agglomeration occurred at high nanofiller contents especially higher than 0.75 wt% in the two-phase nanocomposites. Nanofiller agglomeration was observed to be much lower in the hybrid nanocomposite samples. Therefore, using hybrid nanofillers delays/prevents agglomeration and improves mechanical properties of nanocomposite at the same total filler content.

Numerical Study on the Erosion Characteristics of U-Type Bend for Gas Solid Flow

2017 ◽  
Author(s):  
Yu Wang ◽  
Qi He ◽  
Ming Liu ◽  
Weixiong Chen ◽  
Junjie Yan
Keyword(s):  
Particle Size ◽  
Erosion Rate ◽  
Loading Rate ◽  
Pipe Wall ◽  
Numerical Study ◽  
Pulverized Coal ◽  
Mass Loading ◽  
Two Phase ◽  
Inlet Velocity ◽  
Pipe System

In pulverized coal-fired plant, the U-type bend is commonly used in flue gas and pulverized coal pipe system to due to the constraints of outer space. And gas-solid two-phase flow exists in these pipelines. The erosion of the pipe has significant effect on the safety and reliability of pipelines. In present paper, the erosion characteristics of U-type bend were investigated through CFD (Computational Fluid Dynamics) method. The wear distribution on the pipe wall was obtained. And the particle flow characteristics in U-type bend were analyzed. The influence of inlet velocity, mass loading rate and particle size on the erosion rate was studied as well. Result suggested that the maximum erosion rate increases exponentially with the increase of inlet velocity. And maximum erosion rate increases linearly with the increasing mass loading rate. Increasing particle size can aggravate the wear on the pipe wall.

scholarly journals Coupling Analysis of Fluid-Structure Interaction and Flow Erosion of Gas-Solid Flow in Elbow Pipe

2014 ◽  
Vol 6 ◽  
pp. 815945 ◽  
Author(s):  
Hongjun Zhu ◽  
Hongnan Zhao ◽  
Qian Pan ◽  
Xue Li
Keyword(s):  
Erosion Rate ◽  
Structural Changes ◽  
Fluid Structure Interaction ◽  
Fluid Phase ◽  
Diameter Ratio ◽  
Pipe Diameter ◽  
Discrete Phase Model ◽  
Two Phase ◽  
Fluid Structure ◽  
Structure Interaction

A numerical simulation has been conducted to investigate flow erosion and pipe deformation of elbow in gas-solid two-phase flow. The motion of the continuous fluid phase is captured based on calculating three-dimensional Reynolds-averaged-Navier-Stokes (RANS) equations, while the kinematics and trajectory of the discrete particles are evaluated by discrete phase model (DPM), and a fluid-structure interaction (FSI) computational model is adopted to calculate the pipe deformation. The effects of inlet velocity, pipe diameter, and the ratio of curvature and diameter on flow feature, erosion rate, and deformation of elbow are analyzed based on a series of numerical simulations. The numerical results show that flow field, erosion rate, and deformation of elbow are all sensitive to the structural changes and inlet condition changes. Higher inlet rate, smaller curvature diameter ratio, or smaller pipe diameter leads to greater deformation, while slower inlet rate, larger curvature diameter ratio, and larger pipe diameter can weaken flow erosion.

Experimental Research on Erosion of P110 Tubing during Perforating

2014 ◽  
Vol 1073-1076 ◽  
pp. 2244-2247
Author(s):  
Hu Sun ◽  
Zhi Jun Ning ◽  
Zu Wen Wang ◽  
Zhen Li ◽  
Zhi Guo Wang
Keyword(s):  
Weight Loss ◽  
Erosion Rate ◽  
Large Scale ◽  
Guar Gum ◽  
Electrochemical Corrosion ◽  
Low Velocity ◽  
Gas Field ◽  
Weight Loss Method ◽  
Loss Method ◽  
Gas Fields

Erosion is a main failure of tubings and downhole tools in Changqing gas field. It is necessary to evaluate the erosion rate for the safety of tubing and strings. In this paper, the erosion of P110 steel, in the 0.2%wt guar gum fracturing fluid which contains sands, is investigated by weight loss method in the self-made jet experiment device. It is indicated that the erosion rate increases with the increment of slurry velocity exponentially. When the slurry velocity is in low velocity area, the electrochemical corrosion of dissolved oxygen dominates in erosion mechanism; when slurry velocity increases into middle velocity area, the weight loss is controlled by the synergism of corrosion-erosion; and when the slurry velocity increases into high velocity area, the weight loss rate is dominantly depended on erosion of particles. The results can provide guidelines for large-scale fracturing work of Changqing gas fields.

Determination of Pressure Profile During Closed-Vessel Test Through Computational Fluid Dynamics Simulation

2015 ◽  
Vol 8 (2) ◽  
Author(s):  
Ahmed Bougamra ◽  
Huilin Lu
Keyword(s):  
Solid Propellant ◽  
Time History ◽  
Initial Pressure ◽  
Pressure Profile ◽  
Dynamics Simulation ◽  
Solid Propellants ◽  
Closed Vessel ◽  
Governing Equations ◽  
Two Phase ◽  
Closed Chamber

Two-phase flow modeling of solid propellants has great potential for simulating and predicting the ballistic parameters in closed-vessel tests as well as in guns. This paper presents a numerical model describing the combustion of a solid propellant in a closed chamber and takes into account what happens in such two-phase, unsteady, reactive-flow systems. The governing equations were derived in the form of coupled, nonlinear axisymmetric partial differential equations. The governing equations with customized parameters were implemented into ansys fluent 14.5. The presented solutions predict the pressure profile inside the closed chamber. The results show that the present code adequately predicts the pressure–time history. The numerical results are in agreement with the experiment. Some discussions are given regarding the effect of the grain shape and the sensitivity of these predictions to the initial pressure of the solid propellant bed. The study demonstrated the capability of using the present model implemented into Fluent, to simulate the combustion of solid propellants in a closed vessel and, eventually, the interior ballistic process in guns.

NUMERICAL SOLUTION FOR HYPERBOLIC CONSERVATIVE TWO-PHASE FLOW EQUATIONS

2007 ◽  
Vol 04 (02) ◽  
pp. 299-333 ◽  
Author(s):  
D. ZEIDAN ◽  
A. SLAOUTI ◽  
E. ROMENSKI ◽  
E. F. TORO
Keyword(s):  
Numerical Solution ◽  
Riemann Problem ◽  
Two Phase Flow ◽  
Numerical Dissipation ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Equations ◽  
Flow Problems ◽  
Slope Limiter ◽  
Two Phases

We outline an approximate solution for the numerical simulation of two-phase fluid flows with a relative velocity between the two phases. A unified two-phase flow model is proposed for the description of the gas–liquid processes which leads to a system of hyperbolic differential equations in a conservative form. A numerical algorithm based on a splitting approach for the numerical solution of the model is proposed. The associated Riemann problem is solved numerically using Godunov methods of centered-type. Results show the importance of the Riemann problem and of centered schemes in the solution of the two-phase flow problems. In particular, it is demonstrated that the Slope Limiter Centered (SLIC) scheme gives a low numerical dissipation at the contact discontinuities, which makes it suitable for simulations of practical two-phase flow processes.

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