erosion wear prediction- an qualitative analysis
TRANSCRIPT
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AN INTEGRATED METHODOLOGY FOR PREDICTING MATERIAL
WEAR RATES DUE TO EROSION-CORROSION
A. Gnanavelu, N. Kapur, A. Neville*, J. F. Flores
Institute of Engineering Thermofluids, Surfaces and Interfaces,
School of Mechanical Engineering, University of Leeds, Leeds, United Kingdom, LS2 9JT.
Corresponding author: [email protected]
ABSTRACT
Erosion-corrosion damage within pipelines and associated fluid handling equipment is
prevalent in the oil and gas sector and other process industries where solid-laden flows, such as those
involved in the processing of oil sands, are found. As a first step towards trying to understand theinteractions between erosion and corrosion it is important to understand the erosion damage that
occurs as a result of solid particle impact on a surface (usually metal). This paper addresses this in
relation to transport of fluids in the oil-sands industry. A method for predicting erosion damage has
been developed, using a combination of standard laboratory based experiments and ComputationalFluid Dynamic (CFD) simulations. This involves two stages: (i) a universal wear map is generated
for the material in question using a jet impingement test to generate a wear scar. The local wear rate
from this is interpreted using a CFD simulation of the test to generate a map giving local wear as afunction of particle impact velocity and angle; (ii) a CFD solution is calculated for the pipefitting of
interest giving the particle impact data at each point on the surface. The wear map from the first
stage is then used to give the local wear rate. The power of this method is that once a materialspecific map has been generated then wear on any pipe geometry can be calculated through the
simulation of flow using CFD. In this paper a qualitative comparison is carried out of this method,
and the general applicability is discussed.
Keywords: CFD, Solid particle erosion, erosion-corrosion prediction, particle tracking.
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INTRODUCTION
The economic transportation of slurries plays a vital role in the production of oil in various
industries. To maintain constant production levels, functioning of the hydro-transport equipment is of
utmost importance since failure of the equipment (e.g. pipes, valves, pumps, etc.) leads to economic
consequences and serious safety implications. The probability of failure of plant equipment is high insevere slurry transport conditions. Plant equipment can undergo severe damage due to a variety of
mechanisms, with the most significant being through the mechanism of erosion-corrosion. For
decades, efforts have been made to improve the service life of plant equipment by developingadvanced materials which offer better resistance to material loss. Understanding the conditions in
which this damage mechanism prevails offers a good starting point to develop a predictive tool
which can be used as a guide for material selection. One of the main obstacles for good predictionhas been the lack of understanding of the basic mechanisms, particularly at high solid loadings and in
corrosive fluids. With the advances of technology and the experience gained from field testing,
progress has been made in recent years towards understanding the synergistic effects betweenerosion and corrosion processes and this has significantly improved the ability to predict erosion-
corrosion damage1
. This paper presents an integrated methodology which couples standardlaboratory tests with computational simulations to predict material wear rates due to erosion-
corrosion damage in various equipment. This paper focuses on a qualitative comparison of erosiondamage for a metal coupon in a standard jet impingement test and that for the modified geometry of
an inclined coupon, with CFD used to identify those regions of consistent wear patterns.
METHODOLOGY
A range of standard laboratory tests, such as Coriolis2,3
, Slurry Pot4,5
, ASTM G65/755,6
,Toroid Wheel
7, Jet Impingement
8,9or Pipe Loop
10,11are used by researchers and industrialists to
study the performance of different materials under various conditions of erosion-corrosion.
Traditionally, these laboratory tests have been primarily used to rank material performance.Conversion of this ranking to provide information about erosion-corrosion mechanisms and topredict absolute wear rates in service has proven to be a challenge due to the differences in
conditions between the testing and actual plant equipment12
and also due to uncertainties in the
working conditions experienced in the field13
. Usually lab tests are accelerated wear tests performedon a smaller scale to facilitate an economical and feasible material test programme. Scaling the
results obtained to represent plant equipment has proven to be complicated since the damage
mechanisms might vary with equipment size, in particular the hydrodynamic conditions which leadto particle impact
12. To date, for good prediction of material wear due to erosion, the conditions
simulated in the laboratory need to closely represent the plant conditions leading to damage due to
erosion-corrosion.
Slurry erosion is caused by the interaction of a fluid suspension of solid particles and a targetsurface which experiences loss of material by the repeated impact of the particles. The parts of the
fluid transport system in which erosion is talking place are connected through the flow field which
has a strong influence on the rate of material loss from the target surface. The problem ofunderstanding erosion was summarized by Finnie
14, the erosion of a surface by abrasive particles in
an inert fluid (negligible corrosion) should depend on the number of particles striking the surface,
their velocity and their direction relative to the surface. These quantities are largely determined by
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the prevailing flow conditions15
. Various studies has been conducted to study the effect of flow
conditions on particle impact and it has been proven that the prevailing hydrodynamic condition hasa major effect on the particle impact and hence material removal rates. Studying the prevailing flow
regime provides an insight onto the forces acting on the particles which affect particle motion and
this subsequently determines the conditions of particle impact onto the surface. It had been longconsidered that particle impact angle was the same as the angle at which the inlet flow is directed
towards a test sample; however Benchaita et al. demonstrated that this was not the case16
. With
technological advances in terms of mathematical understanding, it is possible to determine the actual
particle impact angles which are entirely different from the assumed angle, as shown in Figure 1.This is a vital step in developing a model to predict erosion-corrosion wear in plant equipment.
Path of Solid
ParticleActual Impact
Angle
Section A
Impingement
nozzle
Fluid with so lid
particles
Target material
Nominal impact
angle =90 deg90909090
Figure 1. Impact of solid particles in a fluid suspension on a material sample and the difference between the actual angle
and nominal impingement angles.
The method inherent in this work involves two key stages to build a wear map using acombination of standard experimentation and CFD, before predicting actual wear in plant equipment
using a combination of CFD with this wear map.
Stage 1 generating a material specific wear map
a. A set of tests (under standardised conditions) is carried out using a flat coupon of the testmaterial orientated at 90 to the flow in the jet impingement apparatus. Following the test, thecoupon is analysed to give the local wear rate as a function of radial position.
b. A CFD simulation of the jet impingement test, incorporating the motion of the sand particles,is run under the exact conditions from part a, to give the local particle impact velocity andangle.
c. The final part of stage 1 is to generate the universal wear map for the material under test. Thisgives the wear rate as a function of particle impact velocity and particle impact angle.
Stage 2 predicting wear rates in specific geometries
a. A CFD simulation is run for the specific geometry of interest in plant operation. This givesimpact velocity and angle at each position within the geometry.
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b. The wear map from stage 1 is then used to predict the local wear rate at each point. Thisallows the final scar depth and shape to be determined as a function of time, together with theoverall wear of the component.
In this paper, a qualitative comparison is made between the wear profile of a plate under a
standard test orientated at 90 to the flow, and a plate orientated at 15 and 45 to the flow. The CFDmodelling of both scenarios is used to interpret the results. This is a precursor to future work where
quantitative predictions are made using additional data collected about the wear profile of the
samples.
EXPERIMENTATION
A Jet Impingement Test (JIT) rig used to simulate erosion-corrosion conditions has been built
at the University of Leeds, comprising a reciprocating slurry pump, a set of nozzles, sample holders
and a holding tank, which works through impinging a suspension of particles within a liquid onto the
test material9,16
. Figure 2 shows a simple sketch of the experimental setup of the apparatus, togetherwith the geometry of the nozzles, which is used to study the behaviour of various materials under the
erosion/corrosion conditions. If desired, corrosion of the sample can be reduced to negligible values
either by cathodic protection or by reducing oxygen levels in the system17
. The facility enables the
dependence of different input conditions such as the nominal impingement angle, sand concentration,temperature and flow velocity on the erosion rate to be studied and hence to assess the critical
factors which contribute to material removal.
Sample
Water with Sand
ozzle
Pump
7 mm
5 mm
25 mm
Flow Loop
Figure 2. Schematic Diagram of the Slurry JIT used for simulating erosion-corrosion conditions and test the performance
of various material under these conditions.
In the studies reported here, testing was carried out using stainless steel 316L (UNS S31603)
and a non-saline fluid solution (mains water) at room temperature in order to minimise the effect ofcorrosion on the test samples. To ensure minimum effects of corrosion, test samples were
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cathodically protected to prevent material loss due to corrosion. However, it was observed that the
difference in material loss on test samples with and without cathodic protection were negligible inthese conditions and hence further testing was conducted without cathodic protection but with the
assurance of negligible wear due to corrosion in these conditions. All tests were conducted with AFS
50/70 sand which has a nominal size of 212-300m diameter1. The sand concentration was 1% by
weight as measured out of the nozzle prior to impact. It should be noted that 1% does not represent
the sand concentration in the reservoir whereas it represents the actual concentration of sand exiting
the nozzle which was measured for every test. In many studies the sand concentration in the reservoir
is normally quoted as the test condition and this can often be very different (either higher or lowerdepending on the configuration of the apparatus) to the actual concentration exiting the nozzle.
Testing was performed for duration of 120 minutes and each test was repeated three times toensure repeatability. The tests were conducted for three different nominal exit velocities. Figure 3
shows the variation of total weight loss of the material with nominal exit flow velocity. It was seen
that the total weight loss of stainless steel 316L increased linearly with Vn
(where V is the inlet flowvelocity and n in this case was 3). This agreed very well with studies conducted in the past for
steels1,18-20
. This test was conducted to ensure the reliability of the experimental setup and also to
provide data about the impact conditions to be used to develop a CFD model.
y = 0.0566x3.105
R2
= 0.9943
0
10
20
30
40
50
60
70
80
0 2 4 6 8 10 12
Inlet Flow Velocity (m/s)
TotalMassLoss(mg)
Figure 3. Variation of total mass loss of Stainless 316L with different inlet flow velocities.
Following this preliminary work, sand based erosion tests were then carried out using flat
316L samples under similar conditions (1% sand concentration, room temperature and non-saline
fluid) to the previous set but at different nominal impingement angles, namely 15 and 45 from thehorizontal and an inlet velocity of 5m/s. In addition to this, CFD modelling was carried out under
these conditions, as described in the following section.
COMPUTATIONAL MODELLING
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CFD has been widely used in recent years to study and predict the rate of material removal
due to solid particle impact21
. The jet impingement test was simulated using CFD to study the motionof sand particles and the impact conditions prior to impact. As is common with CFD simulations, a
set of assumptions were made whilst performing each simulation:-
1. The shape of the particles was considered to be spherical in order to develop a simple butrobust method.
2. Particle size was assumed to be 300 m which was considered to be a good representation ofthe average size of the sand distribution used for testing.
3. Particle-particle interactions are negligible, which has been shown to be valid assumptionwhile simulating erosion wear at low particle flux
22.
4. The solid phase does not affect the prevailing flow field due to the impingement of the jet onthe flat plate which is attributed to the low particle flux
22.
5. For the configuration of 90 nominal impingement angle, symmetry conditions were used togenerate a half model for the optimum use of computational resource.
6. Particles were released into the flow at zero velocity and at a distance of 10 times thediameter of the nozzle from the tip of the nozzle.
Simulations were performed with various particles in a slurry jet and particle motions
calculated within the flow field. Consistent with the sand used in testing, the density of the particles
was set at 2206 kg/m3.
Figure 4. A half model of the JIT simulation showing the motion path of fluid and solid particles. Solid Particles
(indicated by dotted lines) crossing the fluid streamlines (solid lines) and impacting the target plate. All simulations were
carried out using water, 300 m solid particles of 2206 kg/m 3 density, at 5m/s inlet flow velocity, with a 7mm nozzleand 5mm stand-off nozzle distance.
Figure 4 shows a typical set of results, in this case for a plate at 90 and at a velocity of 5 m/s.The solid lines show the streamlines (that an infinitesimally small particle of the same density as the
water would follow), with the dotted lines showing the motion of the particles. Particles entering the
inlet to the right of the dashed line do not impact the target and have been dragged away by the flow.Those particles entering to the left of the dashed line impact the plate, with particles near the
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stagnation line impacting the plate at high angles whereas the other particles collided at glancing
angles. The results from the simulations provided a whole range of data which included the motionof the particles, position of particles in the flow field and their local velocities. This data can be
interpreted to give the impact velocities and impact angles of individual particles as shown in Figure
5. The variation of impact angles along the length of the sample was consistent with work ofBenchaita et al.
16.
PositionalongYAxis(inmm)
Distance on bottom plate (in mm)
Particle Path
0
0.05
0.1
0.15
0.2
0.75 1 1.25 1.5
V =0.7039 m/s
44.23044.23050
V =0.7039 m/sV = 1.26 m/s
Figure 5. Impact angle and Impact velocity of solid particle impacting the bottom plate extracted from a JIT simulation
carried out at 90 nominal impingement angle at conditions stated in Figure 4.
Figures 6 and 7 show impact velocity and impact angles as function of position along the testplate and it can be observed that particles closer to the stagnation line (Y-axis) impact the target at
low velocity due to the drag force exerted by the decelerating fluid and at high angles whereas
particles away from the stagnation line impact at higher velocities as the fluid starts accelerating and
at glancing angles23
. This highlights the variation in impact velocity and angles across the plate.Finally, Figure 8 shows the variation of impact velocities against impact angles demonstrating that
part of the wear map capable of being simulated with the JIT under these flow conditions.
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
0 1 2 3 4 5 6 7 8 9 10
Position on test plate away from the centre of plate (in mm)
Particleimpactvelocity(m/s)
Figure 6. Variation of particle impact velocities as a function of position obtained from a JIT simulation carried out at
90 nominal impingement angle at conditions stated in Figure 4.
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0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
0 1 2 3 4 5 6 7 8 9 10
Position on test plate away from the centre of plate (in mm)
Particleim
pactangles(indegrees)
Figure 7. Variation of particle impact angles as a function of position along the length of the specimen in a JIT simulation
at conditions stated in Figure 4.
Impingement rig simulation
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
0 10 20 30 40 50 60 70
Particle impact angles (in degrees)
P
articleimpactvelocity(inm/s)
Figure 8. Particle impact velocities and angles that can be simulated using this configuration of the JIT at conditions
stated in Figure 4.
TEST RESULTS AND DISCUSSION
The samples from the impingement tests performed at 90, 45 and 15 were analysed using
Scanning Electron Microscopy (SEM) to study the nature of the complete wear scar and individualwear scars due to discrete particle impacts. The regions of scarring were characterised using the
results from the CFD. CFD simulations of the jet impingement test provided data regarding the range
of impact angles (shown in Figure 8), and this can be used to predict the type of local impact andwear patterns based on previous studies of erosion of a ductile material
14,24-26. Based on the type of
particle impact and local material wear removal, the entire wear scar can be divided into three main
regions as a result of impact angle and velocity for a ductile material:
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Region 1 is characterised on the basis of particles impacting the surface at high angles which
lead to the formation of flakes due to plastic deformation and the removal of these flakes due toimpact by approaching particles. This region in the jet impingement test is mainly concentrated
around the stagnation point as shown in Figure 9. The stagnation point is the intersection of the
symmetrical axis and the horizontal plate and is defined by high static pressures and very low flowvelocities. Since the flow vector changes rapidly the viscosity effects of the fluid are low and hence
the tendency for particles to cross fluid streamlines in this region due to particle inertia is high, which
leads to high angle particle impacts23
. Since the fluid in this region is decelerating, there is a drop in
flow velocity which causes the oncoming particles to slow down and hence the particle impactvelocities in this region are low
23(10% of the inlet flow velocity for this particular condition). Figure
10 shows a description of the mechanism by which material is removed due to plastic deformation
caused by particles impacting at high angles.
Line of
symmetry
Inlet flow pipe
modelled in CFD
Particle
motion
Region 1 Region 2 Region 3
Test
Surface
Impinging
inlet flow
Fluid flow regime
Reformed fluid jet
Flow direction
High
turbulence
region
Figure 9. Prevailing fluid regime around the test sample in a JIT as simulated using CFD, divided into three regions and
motion of solid particles in the flow field.
Region 2 can be characterised by particles impacting at medium to low angles in the range of
(40-10). Region 2, shown in Figure 9, is a region of high turbulence which is due to the increase influid momentum as the fluid moves away from the stagnation region. Increase in fluid momentumprovides energy to the solid particles and the direction of the flow tends to deter the particle away
from the sample. However, the inertia of particles tends to drive the particles towards the surface of
the sample causing impact. Particle impacts in this region are of higher velocities but at impact
angles lower than those experienced in region 1. The reduction in impact angles is due to thealignment of the flow into a jet that lies parallel to the plate. Fluid motion causes a drag on the
particles in a stream wise direction and hence the tendency of the solid particles to cut across fluid
streamlines is reduced compared to region 1. The mechanism in which material is removed in thisregion is due to ploughing action and micro cutting as noted by Hutchings
24. The majority of the
impacts are at medium to low angles which causes the flakes to be formed in a predominant
direction; along the direction of fluid flow, as shown in Figure 10.
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High
angle
impact
Flake
formation
Plastic deformation due
to High impact angles
Medium -Low
angle impact
Flake formation
towards flow
direction
Plastic deformation due to
medium-low impact angles
Figure 10. Material removal mechanism due to impact of solid particles at high and medium to low impact angles for a
ductile material14,24-26 in this case stainless steel 316L.
Region 3 is the area where the fluid flow dominates particles motion, i.e. particles almost
completely follow the streamlines which leads to lesser impacts and hence has minor effect on the
erosion rates of the target material. In this region, the flow jet increases and turbulence energy decaysto the surroundings. The fluid flow represents a jet but in the radial direction. Solid particles align
themselves in an orderly manner with the fluid streamlines and impacts are very minimal. Particles
that do impact in this region glance or slide along the surface in a scratching motion. Local fluidvelocities are quite high as the flow develops completely into a jet. This region has a minimum
contribution to material loss due to wear caused by particle impact however the effects of flow
induced corrosion might be high27
. The effects of corrosion in this study has been minimised to
negligible levels, however as a precursor to future studies, this region needs to be carefully studiedfor the effect of corrosion.
The three regions can be characterised as:
Region 1: Impact angle 90 to 40 Region 2: Impact angle 40 to 20 Region 3: Impact angle < 20
Now that three distinct regions based on the type of particle impact has been defined, the
surface of the samples from three different tests (90, 45and 15) were observed under a SEM to
asses the actual nature of the local impacts and wear patterns. Figure 11 shows the top view of a 90impingement test specimen. Three concentric regions were observed (as outlined in the Figure 11)
and these were categorized as regions 1, 2 and 3 based upon the particle impact data obtained fromCFD simulations.
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Particles impacts s imulated using CFD
1 32 4
3
1
2
Visual observation of 90
impingement test sample
25 mm
Figure 11. Top view of the test sample after testing viewed under the naked eye indicating three distinctive regions of
wear and also the CFD predictions of particle motion in the JIT.
Figure 11 also shows a half computational model of the jet impingement test with the motionof particles indicated by line-arrows. The test surface is divided in four regions, three based on local
particle impact angles as described earlier with an additional area, where the amount of particle
impacts are minimum and hence material wear due to impact erosion, is also defined and is known asregion 4. The SEM photos of the three regions are shown in Figures 12-14. Figure 12 indicates the
local wear pattern very close to the stagnation point, in region 1. Area A in the picture indicates
individual particle impact and B shows the flakes which are formed plastically due to particle
impacts. The appearance of the flakes, which are spread out evenly around a impact region, indicatesmaterial damage due to high angle impacts as described in Figure 10.
Figure 12. SEM photo of a 90 impingement test sample very close to the stagnation point, in region 1 as shown in
Figure 11. Area A indicates individual particle impact and B shows the material flakes generated due to plastic
deformation induced by particle impacts.
A B
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Figure 13 shows a SEM photo of the post-test sample surface on region 2. CFD simulations
predict particles to impact at medium-low angles. Area C shows the region of heavy indentation andit can be seen that flakes of material are formed around the impact region. This indicates that the
region was impacted by particles at high angles. Area D, which is further away from the centre but
still in region 2 shows flakes which were formed due to impact of particles. The deformation of thesurface is along the direction of fluid flow indicating a removal mechanism where the material is
been deformed towards one direction as shown in Figure 10. This is in close proximity to CFD
simulations which predict impact of particles at medium-low angles in this region.
Flow
Direction
C
D
Figure 13. SEM photo of a 90 impingement test sample of the local wear pattern in region 2. Area C indicates material
flakes formed due to particle impacts and D shows the flakes of material aligned to flow direction.
Figure 14 shows a SEM picture of the local wear pattern in region 3, where the CFD
simulations indicate impact by particles at low and glancing angles. Area E indicates particle impact
and it could be clearly observed that the material has been deformed along the direction of the flow.
Area F indicates an individual impact region, where the local impact scar is quite lengthy whichindicates that particle impacts were at very low angles, as predicted by CFD simulations.
Flow direction
E
F
Figure 14. SEM photo of a 90 impingement test sample of the local wear pattern in region 3. Area E indicates material
flakes formed due to particle impacts and F shows a long shallow crater formed due to low angle impacts.
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Similarly, the wear scar on the surface of a sample from a 15 impingement test was divided
into three distinct regions, defined by particle impact angles predicted by CFD simulation as shownin Figure 15. These regions were then examined using SEM to observe the morphology of the impactregions and craters.
3
1
2
Visual observation of 15
impingement test sample
1 2 32
Particles impacts simulated using CFD
25 mm
Figure 15. Top view of a post-test sample viewed under the naked eye indicating three distinctive regions of wear and
also the CFD predictions of particle motion in the JIT at 15along the horizontal.
SEM pictures of the three regions of the wear scar are shown in Figures 16-18. Figure 16
shows the local wear pattern on region 1 on the post-test sample where plastic deformation andheavy indentations (shown by area A) due to high angle impacts are high.
Flow
directionG
Region 1
Figure 16. SEM picture of the wear pattern in region 1 where area A indicates surface indentation due to high angle
impact and plastic deformation of material.
Figure 17 shows the local wear craters in region 2 observed under a SEM. Unlike the otherregions, the direction on the flow is angled in this picture since this region was away from the centre
line (where the flow is along the length of the sample) but the area covered was within region 2. This
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picture clearly shows the deformed material aligned with the flow asserting the fact that particle
impacts occurred at medium-low angles. Figure 18 shows the wear pattern in region 3 where theparticles are predicted to impact by glancing or sliding angles from CFD simulations. On comparing
Figure 17 and18, it can be seen that material damage is not as severe in region 3 as compared to
region 2. Surface indentations are less compared to region 2 signifying sliding angle impacts leadingto scratches on the surface.
Flow
direction
Region 2
Figure 17. SEM picture of the wear pattern in region 2 showing surface indentations and crater along the direction of
fluid flow.
Flow
direction
Region 3
Figure 18. SEM picture of the wear pattern in region 3 showing surface indentations and crater along the direction of
fluid flow.
Finally, CFD simulations were conducted for a JIT configuration having a specimen angled at
45. Under this condition the flow can be predominantly divided into two regions-region 2 and
region 3, with the region of impacts close to 90 being relatively small in number.
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3
2
Visual observation of 45
impingement test sample
2
3
Particl es impacts simulated using CFD
25 mm
Figure 19. Top view of a post-test sample viewed under the naked eye indicating two distinctive regions of wear and also
the CFD predictions of particle motion in the JIT at 45along the horizontal.
Observing region 2 of the surface using a SEM, shown in Figure 20 at two different positions
for local wear pattern, it was seen that predominant flakes formed due to plastic deformation ofmaterial was aligned along the direction of fluid flow. Impacts leading to heavy indentation were
hardly seen, emphasizing minimal particle impacts at high angles as predicted by CFD simulations.
Region 2
Position 1
Flow
direction
Region 2
Position 2
Flow
direction
Figure 20. SEM photos of the local wear pattern in region 2 (region defined by medium-low particle impact angles using
CFD predictions) at two different positions.
Figure 21 shows SEM images of the surface of the test sample on region 3 at two different
positions. CFD simulation data predicted particles to impact the surface at low-sliding angles andthis can be see from long craters as indicated by H in Figure 21. The flakes formed by material
deformation is well directed towards flow direction, which stresses the fact that particles in this
region impacted at very low angles as predicted by CFD simulations.
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Region 3
Position 1
Flow
direction
Region 3
Position 2
Flow
direction
Figure 21. SEM photos of the local wear pattern in region 3 (region defined by low-sliding particle impact angles by
CFD predictions) at two different positions.
CONCLUSION
CFD simulations of the JIT were used to define various regions on the wear scar depending
upon the type of individual particle impacts (high, medium and low). Actual JIT were conducted at
three different nominal impingement angles (90, 45 and 15) and the wear scar within was
observed under a SEM for local indentations to study the type of local material degradation. It was
observed that the mechanism leading to local material degradation was similar to those predicted byCFD simulations of particle impacts.
The results show that the CFD model can be used to successfully interpret the results of thetests run under different angles, and that for a given test it is possible to define the local conditions
that exist on the plate.
The final stage of this work is to introduce wear rates based on local conditions, fromexperiment. This will then provide a method where, performing a small number of practical tests on
the JIT, the wear rate on actual plant components can be predicted. Further development of this
method are ongoing to include the effects of flow induced corrosion and to predict material wear dueto erosion-corrosion in plant equipment.
H
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