The Effects of Surface Treatments on Solid Particle Erosion of 12Cr Steels for USC Power Plants

2006 ◽  
Vol 118 ◽  
pp. 201-208
Author(s):  
Kee Won Urm ◽  
Sun Ho Lee ◽  
J.W. Lee ◽  
E.Y. Lee
Keyword(s):  
Solid Particle ◽  
Impact Angle ◽  
Surface Treatments ◽  
Solid Particles ◽  
Solid Particle Erosion ◽  
Particle Erosion ◽  
Hvof Spray ◽  
Bare Steel ◽  
The Impact ◽  
Turbine Bucket

12Cr steels have been applied on the turbine bucket and nozzle partition materials for the ultra super critical (USC) coal-fired power plant. Turbine bucket and nozzle materials are damaged by the solid particles within USC steam conditions. Therefore, they have been protected by the surface treatments such as ion nitriding, boriding and chrome carbide high velocity oxygen fuel (HVOF) spray coating. In this study, the surface treatment effects on the solid particle erosion (SPE) characteristic of 12Cr steels were examined in the temperature range of 540 to 620°C and the mechanisms of surface damage are investigated. The SPE of 12Cr steel originated from micro cutting, whereas, that of boriding and chrome carbide HVOF spray originated from the repeated collision, crack initiation and propagation. In case of 12Cr bare steel, the erosion of soft materials occurred in the impact angle range of 30° to 60° at test temperatures. The SPE resistances of boride and HVOF treated steels in the impact angle range of 30° to 60° at 593°C and 621°C were much higher than those of 12Cr bare steel.

Numerical Prediction of Solid Particle Erosion for Elbows Mounted in Series

2014 ◽  
Author(s):  
Frederic N. Felten
Keyword(s):  
Solid Particle ◽  
Volume Concentration ◽  
Flow Path ◽  
Solid Particles ◽  
Critical Parameters ◽  
Solid Particle Erosion ◽  
Surface Erosion ◽  
Particle Erosion ◽  
In Series ◽  
The Impact

Erosive wear due to solid-particle impact is a complex phenomenon where different parameters are responsible for causing material removal from the metal surface. Some of the most critical parameters regarding the solid particles are the size, density, roundness, and volume concentration. The properties of the carrying fluid (density, dynamic viscosity, bulk modulus…), the geometry of the flow path (straight or deviated), and the surface material properties are also major contributors to the overall severity of the solid-particle erosion process. The intent of this paper is to focus on the impact of the flow path geometry on surface erosion for a specific carrier fluid, flow rate, sand type and sand-volume concentration. A numerical approach using the commercial CFD code FLUENT is applied to investigate the solid particle erosion in two 90° pipe elbows mounted in series. The distance between the two elbows is varied, as is the angle between them. A total of 16 cases are analyzed numerically. The relationships between the parameters pertinent to the two elbows and the erosion pattern, erosion intensity, and location of maximum erosion are presented. Prior to the analyses for the two elbows mounted in series, an in-depth validation effort for a single elbow geometry is undertaken to determine the appropriate mesh requirement, turbulence model, and to calibrate the inputs to the erosion model.

Experimental Investigation on the Solid Particle Erosion in the Control Stage Nozzles of Steam Turbine

2007 ◽  
Author(s):  
Shunsen Wang ◽  
Guanwei Liu ◽  
Jingru Mao ◽  
Zhenping Feng
Keyword(s):  
Life Cycle ◽  
Steam Turbine ◽  
Solid Particle ◽  
Erosion Rate ◽  
Impact Angle ◽  
Solid Particle Erosion ◽  
Particle Erosion ◽  
Control Stage ◽  
Profile Characteristic ◽  
The Impact

This study is concerned with experiments for the relation of solid particle erosion (SPE) and the nozzle profiles. The exfoliated scale from boiler tubing results in hard particles that erode steam turbine components, especially on the control stage nozzles of high parameters turbine. To characterize SPE, solid particle trajectory is measured using particle image velocimetry (PIV) and its relation with the erosion rate of the nozzle surfaces is correlated. In addition, erosion characteristic of nozzle material is investigated by experiments and results reveal that the erosion rate is directly proportional to the impacting velocity of particles with the power of 2.31 and the maximum erosion rate is taken place at the impact angle of 20–25 degree. Furthermore, 0.5% increase in the erosion rate for every one degree of steam temperature rise is observed in the range of 839K∼883K. The erosion rate of front-loaded nozzle A is 2∼3 times higher than that of conventional design nozzle B. The life cycle of nozzle is determined by the erosion of outlet edge, and the life of nozzle B is about 5 times as long as the life of nozzle A. Based on the relation of erosion rate and nozzle profile characteristic, it can be inferred that a aft-loaded nozzle with a contoured endwall substituting a planar endwall may outperform over other nozzle profiles in anti-SPE, prolonging the life cycle of the nozzle.

Research on Solid Particle Erosion Behaviors of TC4 Alloy at Different Erosion Angles

2014 ◽  
Vol 1049-1050 ◽  
pp. 167-170
Author(s):  
Bao Hui Guo
Keyword(s):  
Solid Particle ◽  
Erosion Rate ◽  
Impact Angle ◽  
Large Impact ◽  
Solid Particle Erosion ◽  
Particle Erosion ◽  
Erosion Mechanism ◽  
Tc4 Alloy ◽  
Impact Angles ◽  
The Impact

The solid particle erosion behaviors of TC4 Alloy were studied at different erosion angles. The results show that the erosion rate of TC4 alloy at impact angle 30o was higher than those at the impact angles of both 60o and 90o. At low impact angle, the erosion mechanism could be concluded as grinding erosion and furrow erosion. However, the erosion mechanism could be fatigue erosion at large impact angle.

scholarly journals Resistance of PVD Coatings to Erosive and Wear Processes: A Review

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 921
Author(s):  
Alicja Krella
Keyword(s):  
Wear Rate ◽  
Solid Particle ◽  
Coefficient Of Friction ◽  
Cavitation Erosion ◽  
Solid Particles ◽  
Solid Particle Erosion ◽  
Pvd Coatings ◽  
Particle Erosion ◽  
Tribological Tests ◽  
Hydraulic Machines

Due to the increasing maintenance costs of hydraulic machines related to the damages caused by cavitation erosion and/or erosion of solid particles, as well as in tribological connections, surface protection of these components is very important. Up to now, numerous investigations of resistance of coatings, mainly nitride coatings, such as CrN, TiN, TiCN, (Ti,Cr)N coatings and multilayer TiN/Ti, ZrN/CrN and TN/(Ti,Al)N coatings, produced by physical vapor deposition (PVD) method using different techniques of deposition, such as magnetron sputtering, arc evaporation or ion plating, to cavitation erosion, solid particle erosion and wear have been made. The results of these investigations, degradation processes and main test devices used are presented in this paper. An effect of deposition of mono- and multi-layer PVD coatings on duration of incubation period, cumulative weight loss and erosion rate, as well as on wear rate and coefficient of friction in tribological tests is discussed. It is shown that PVD coating does not always provide extended incubation time and/or improved resistance to mentioned types of damage. The influence of structure, hardness, residence to plastic deformation and stresses in the coatings on erosion and wear resistance is discussed. In the case of cavitation erosion and solid particle erosion, a limit value of the ratio of hardness (H) to Young’s modulus (E) exists at which the best resistance is gained. In the case of tribological tests, the higher the H/E ratio and the lower the coefficient of friction, the lower the wear rate, but there are also many exceptions.

scholarly journals Effect of Silicon Addition on High-Temperature Solid Particle Erosion-Wear Behaviour of Mullite-SiC Composite Refractories Prepared by Nitriding Reactive

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaochao Li ◽  
Shusen Chen ◽  
Zhaohui Huang ◽  
Minghao Fang ◽  
Yan’gai Liu ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Solid Particle ◽  
Elevated Temperatures ◽  
Silicon Powder ◽  
Wear Behaviour ◽  
Solid Particle Erosion ◽  
Erosion Wear ◽  
Particle Erosion ◽  
Powder Addition ◽  
The Impact

Solid particle erosion-wear experiments on as-prepared mullite-SiC composite refractories by nitriding reactive sintering were performed at elevated temperatures, using sharp black SiC abrasive particles at an impact speed of 50 m/s and the impact angle of 90° in the air atmosphere. The effects of silicon powder addition and erosion temperature on the erosion-wear resistance of mullite-SiC composite refractories were studied. The test results reveal that Si powders caused nitriding reaction to formβ-sialon whiskers in the matrix of mullite-SiC composite refractories. The erosion-wear resistance of mullite-SiC composite refractories was improved with the increase of silicon powder addition and erosion temperature, and the minimum volume erosion rate was under the condition of 12% silicon added and a temperature of 1400°C. The major erosion-wear mechanisms of mullite-SiC composite refractories were brittle erosion at the erosion temperature from room temperature to 1000°C and then plastic deformation from 1200°C to 1400°C.

Representative volume element-based simulation of multiple solid particles erosion of a compressor blade considering temperature effect

2019 ◽  
Vol 234 (8) ◽  
pp. 1173-1184
Author(s):  
Bijan Mohammadi ◽  
AmirSajjad Khoddami
Keyword(s):  
Finite Element ◽  
Solid Particle ◽  
Representative Volume Element ◽  
Erosion Rate ◽  
Compressor Blade ◽  
Volume Element ◽  
Solid Particles ◽  
Solid Particle Erosion ◽  
Particle Erosion ◽  
Representative Volume

Solid particle erosion is one of the main failure mechanisms of a compressor blade. Thus, characterization of this damage mode is very important in life assessment of the compressor. Since experimental study of solid particle erosion needs special methods and equipment, it is necessary to develop erosion computer models. This study presents a coupled temperature–displacement finite element model to investigate damage of a compressor blade due to multiple solid particles erosion. To decrease the computational cost, a representative volume element technique is introduced to simulate simultaneous impact of multiple particles. Blade has been made of Ti-6Al-4V, a ductile titanium-based alloy, which is impacted by alumina particles. Erosion finite element modeling is assumed as a micro-scale impact problem and Johnson–Cook constitutive equations are used to describe Ti-6Al-4V erosive behavior. In regard to a wide variation range in thermal conditions all over the compressor, it is divided into three parts (first stages, middle stages, and last stages) in which each part has an average temperature. Effective parameters on erosive behavior of the blade alloy, such as impact angle, particles velocity, and particles size are studied in these three temperatures. Results show that middle stages are the most critical sites of the compressor in terms of erosion damage. An exponential relation is observed between erosion rate and particles velocity. The dependency of erosion rate on size of particles at high temperatures is indispensable.

scholarly journals Particle-Based Numerical Simulation Study of Solid Particle Erosion of Ductile Materials Leading to an Erosion Model, Including the Particle Shape Effect

Materials ◽  
2021 ◽  
Vol 15 (1) ◽  
pp. 286
Author(s):  
Shoya Mohseni-Mofidi ◽  
Eric Drescher ◽  
Harald Kruggel-Emden ◽  
Matthias Teschner ◽  
Claas Bierwisch
Keyword(s):  
Solid Particle ◽  
Particle Shape ◽  
Solid Particles ◽  
Solid Particle Erosion ◽  
Shape Effect ◽  
Particle Erosion ◽  
Erosion Model ◽  
Ductile Materials ◽  
Erosion Behavior ◽  
Numerical Predictions

Solid particle erosion inevitably occurs if a gas–solid or liquid–solid mixture is in contact with a surface, e.g., in pneumatic conveyors. Having a good understanding of this complex phenomenon enables one to reduce the maintenance costs in several industrial applications by designing components that have longer lifetimes. In this paper, we propose a methodology to numerically investigate erosion behavior of ductile materials. We employ smoothed particle hydrodynamics that can easily deal with large deformations and fractures as a truly meshless method. In addition, a new contact model was developed in order to robustly handle contacts around sharp corners of the solid particles. The numerical predictions of erosion are compared with experiments for stainless steel AISI 304, showing that we are able to properly predict the erosion behavior as a function of impact angle. We present a powerful tool to conveniently study the effect of important parameters, such as solid particle shapes, which are not simple to study in experiments. Using the methodology, we study the effect of a solid particle shape and conclude that, in addition to angularity, aspect ratio also plays an important role by increasing the probability of the solid particles to rotate after impact. Finally, we are able to extend a widely used erosion model by a term that considers a solid particle shape.

A Statistical Approach for Modeling Stochastic Rebound Characteristics of Solid Particles

2019 ◽  
Author(s):  
G. Haider ◽  
A. Asgharpour ◽  
J. Zhang ◽  
S. A. Shirazi
Keyword(s):  
Experimental Data ◽  
Solid Particle ◽  
Oil And Gas ◽  
Great Influence ◽  
Solid Particles ◽  
Process Equipment ◽  
Particle Impact ◽  
Solid Particle Erosion ◽  
Contributing Factors ◽  
Particle Erosion

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.

A Combined CFD-Mechanistic Approach for Predicting Solid Particle Erosion in Annular Flow in Pipe Fittings and Elbows

2020 ◽  
Author(s):  
Farzin Darihaki ◽  
Elham Fallah Shojaie ◽  
Jun Zhang ◽  
Siamack A. Shirazi
Keyword(s):  
Multiphase Flow ◽  
Solid Particle ◽  
Annular Flow ◽  
Large Diameter ◽  
Solid Particles ◽  
Wall Material ◽  
Solid Particle Erosion ◽  
Flow Conditions ◽  
Particle Erosion ◽  
Wide Range

Abstract In internal flows, solid particles carried by the fluid could damage pipelines and fittings. Particles that are entrained in the fluid can cross streamlines and transfer a part of their momentum to the internal surface by impacts and cause local wall material degradation. Over the past decades, a wide range of models is introduced to predict particle erosion which includes empirical models, mechanistic models, and CFD which is currently the state-of-art numerical approach to simulate the erosion process. Multiphase flow under annular flow conditions adds to the complexity of the model. Although with the current computational capabilities transient CFD models are effectively applicable, this type of transient multiphase approach is not practical yet for engineering prediction of erosion especially for the large diameter applications with huge computational domains. Therefore, the presented combined approach could be utilized to obtain erosion rates for large diameter cases. Thus, an approach combining CFD and mechanistic multiphase models characterizing annular flow is developed to predict solid particle erosion. Different factors including film thickness in pipes and fittings which are affecting erosion under gas-dominated multiphase flow conditions are investigated. The results from the current approach are compared to experimental data and transient CFD simulations for annular flow in elbows showing a very good agreement with both.

Investigation of Particle Size Effects on Solid Particle Erosion of Elbows in Series for Liquid-Solid Flows

2021 ◽  
Author(s):  
Yeshwanthraj Rajkumar ◽  
Soroor Karimi ◽  
Siamack A. Shirazi
Keyword(s):  
Particle Size ◽  
Solid Particle ◽  
Size Effects ◽  
Oil And Gas ◽  
Solid Particles ◽  
Solid Particle Erosion ◽  
Particle Sizes ◽  
Particle Erosion ◽  
Particle Size Effects ◽  
In Series

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.

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