ANSYS Confernce on Fatigue Life
Transcript of ANSYS Confernce on Fatigue Life
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Predicting Fatigue Life with ANSYS
WorkbenchHow To Design Products That Meet Their Intended Design
Life Requirements
Predicting Fatigue Life with ANSYS
WorkbenchHow To Design Products That Meet Their Intended Design
Life Requirements
Raymond L. Browell, P. E.Product Manager New TechnologiesANSYS, Inc.
Al HancqDevelopment EngineerANSYS, Inc.
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Fatigue Agenda
General Fatigue Review
Fatigue Analysis in Workbench Working with Legacy Models
Optimization with Fatigue Fatigue Within Workbench Fits Into
Everyones Process! Questions and Answers
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General Fatigue Review
Why Fatigue Analysis?
While many parts may work well initially,they often fail in service due to fatiguefailure caused by repeated cyclic loading
In practice, loads significantly below staticlimits can cause failure if the load isrepeated sufficient times
Characterizing the capability of a materialto survive the many cycles a component
may experience during its lifetime is theaim of fatigue analysis
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General Fatigue Review
Common Decisionsfor Fatigue AnalysisFatigue Analysis
Type
Loading Type
Mean Stress Effects
Multiaxial StressCorrection
Fatigue ModificationFactor
Fatigue Analysis Type
Loading Type
Mean Stress Effects
Multiaxial StressCorrection
Fatigue Modifications
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General Fatigue Review
Fatigue Analysis Types
Strain Life(Available in ANSYS Fatigue Module)
Stress Life
(Available in ANSYS Fatigue Module)
Fracture Mechanics
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General Fatigue Review
Strain Life
Strain can be directly measured and has been shown to
be an excellent quantity for characterizing low-cyclefatigue
Strain Life is typically concerned with crack initiation
In terms of cycles, Strain Life typically deals with arelatively low number of cycles and therefore addressesLow Cycle Fatigue (LCF), but works with high numbers
of cycles as wellLow Cycle Fatigue usually refers tofewer than 105 (100,000) cycles
The Strain Life approach is widely usedat present
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Strain Life
( ) ( )cff
b
f
f
NNE
22'
'
2
+=
n
KE
'/1
'2
+=
The Strain Life Relation equationis shown below:
The two cyclic stress-strain parametersare part of the equation below:
2
E
Nf
Nf2
= Total Strain Amplitude
= 2 x the Stress Amplitude
= Modulus of Elasticity
= Number of Cycles to Failure
= Number of Reversals to Failure
'
f
'
f
K'
n'
= Fatigue Strength Coefficient
B = Fatigue Strength Exponent(Basquins Exponent)
= Fatigue Ductility Coefficient
C = Fatigue Ductility Exponent
= Cyclic Strength Coefficient
= Cyclic Strain Hardening Exponent
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General Fatigue Review
Strain Life
For Strain Life, the total strain (elastic +plastic) is the required input
But, running an FE analysis to determine
the total response can be very expensiveand wasteful, especially if the nominalresponse of the structure is elastic
So, an accepted approach is to assume anominally elastic response and then makeuse of Neubers equation to relate local
stress/strain to nominal stress/strain at astress concentration location
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Strain Life
SeKt2
=
To relate strain to stress we use Neubers Rule, which is shown below:
Kt
e
S
= Local (Total) Strain
= Local Stress
= Elastic Stress Concentration Factor
= Nominal Elastic Strain
= Nominal Elastic Stress
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Strain Life
Simultaneously solving Neubers equation alongwith cyclic strain equation, we can calculate thelocal stress/strains (including plastic response)given only elastic input
Note that this calculation is nonlinear and is solvedvia iterative methods
ANSYS fatigue uses a value of 1 for Kt, assumingthat the mesh is refined enough to capture anystress concentration effects
Note: This Kt is not be confused with the Stress
Reduction Factor option which is typically used in Stresslife analysis to account for things such as reliability andsize effects
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General Fatigue Review
Stress Life
Stress Life is based on S-N curves (Stress Cycle
curves)Stress Life is concerned with total life and does not
distinguish between initiation and propagation
In terms of cycles, Stress Life typically deals with arelatively High number of cycles
High number of cycles is usually refers to more than
105 (100,000) cyclesStress Life traditionally deals with
relatively high numbers of cycles and
therefore addresses High Cycle Fatigue(HCF), greater than 105 cycles inclusiveof infinite life
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Fracture Mechanics Fracture Mechanics starts with an assumed flaw of known
size and determines the cracks growth Facture Mechanics is therefore sometimes referred to as
Crack Life
Facture Mechanics is widely used to determine inspection
intervals. For a given inspection technique, the smallestdetectable flaw size is known. From this detectable flaw sizewe can calculate the time required for the crack to grow to acritical size. We can then determine our inspection intervalto be less than the crack growth time.
Sometimes, Strain Life methods are used to determine crackinitiation with Fracture Mechanics used to determine thecrack life therefore:
Crack Initiation + Crack Life = Total Life
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ANSYS Fatigue Module
Integrated into the ANSYS Workbench EnvironmentANSYS Fatigue Module is able to further leverage
advances that the ANSYS Workbench offers such as:
CAD support including Bi-Directional Parameters
Solid Modeling
Virtual Topology
Robust Meshing
Hex-Dominant Meshing
Automatic Contact Detection
Optimization
Design for Six Sigma Robust Design that the ANSYS Workbench offers
Fatigue Analysis in Workbench
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Strain Life Decisionsfor Fatigue Analysis
Loading Type
Mean Stress Effects
Multiaxial StressCorrection
Fatigue Modification
Factor
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Stress LifeDecisions forFatigue Analysis
Loading Type
Mean Stress EffectsMultiaxial Stress
Correction
Fatigue ModificationFactor
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Loading Types
Constant amplitude, proportional loadingConstant amplitude, non-proportional
loading
Non-constant amplitude, proportionalloading
Non-constant amplitude, non-proportionalloading
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Constant amplitude, proportional loading
Loading is of constant amplitude because onlyone set of FE stress results along with aloading ratio is required to calculate the
alternating and mean values
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Constant amplitude, proportional loading
Is the classic, back of the envelopecalculation describing whether the load has aconstant maximum value or continually varies
with timeThe loading ratio is defined as the ratio of thesecond load to the first load (LR = L2/L1)
Common types of constant amplitude loadingare: Fully reversed (apply a load, then apply an equal
and opposite load; a load ratio of 1) Zero-based (apply a load then remove it; a load ratioof 0)
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Constant amplitude, proportional loading
Loading is proportional since only one set of FEresults are needed (principal stress axes do notchange over time)
Since loading is proportional, looking at a singleset of FE results can identify critical fatiguelocations.
Since there are only two loadings, no cyclecounting or cumulative damage calculations
need to be done
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Constant amplitude, non-proportional loadingLooks at exactly two load cases that need not be
related by a scale factorAnalyses where loading is proportional but results
are not
The loading is of constant amplitude but non-proportional since principal stress or strain axesare free to change between the two load sets
This happens under conditions where changingthe direction or magnitude of loads causes achange in the relative stress distribution in themodel. This may be important in situations with
nonlinear contact, compression-only surfaces, orbolt loads
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Constant amplitude, non-proportional loading
This type of fatigue loading can describe commonfatigue loadings such as:
Alternating between two distinct load cases (like abending load and torsional load)
Applying an alternating load superimposed on a staticload
No cycle counting needs to be done
But since the loading is non-proportional, thecritical fatigue location may occur at a spatiallocation that is not easily identifiable by looking at
either of the base loading stress states
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Fatigue tools located under asolution branch are inherentlyapplied to that single branchand thus can only handle
proportional loading In order to handle non-
proportional loading, the fatigue
tool must be able to spanmultiple solutions
This is accomplished by adding afatigue tool under the solution
combination folder that canindeed span multiple solutionbranches
Constant amplitude, non-proportional loading
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Non-constant amplitude, proportional loading Instead of using a single load ratio to calculate alternating and
mean values, the load ratio varies over time Think of this as coupling an FE analysis with strain-gauge results
collected over a given time interval
Since loading is proportional, the critical fatigue location can be
found by looking at a single set of FE results
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Fatigue Analysis in Workbench
Non-constant amplitude,proportional loading
However, the fatigue loadingwhich causes the maximumdamage cannot easily be seen
Thus, cumulative damagecalculations (including cycle
counting such as Rainflow anddamage summation such asMiners rule) need to be doneto determine the total amountof fatigue damage and which
cycle combinations cause thatdamage
Cycle counting is a means toreduce a complex load historyinto a number of events, whichcan be compared to theavailable constant amplitudetest data
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Fatigue Analysis in Workbench
Non-constant amplitude, proportional loading
The ANSYS Fatigue Module uses a quick
counting technique to substantially reduceruntime and memory
In quick counting, alternating and mean stresses
are sorted into bins before partial damage iscalculated
Without quick counting, data is not
sorted into bins until after partialdamages are found
The accuracy of quick counting is
usually very good if a proper numberof bins are used when counting
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Strictly speaking, bin size
specifies the number ofdivisions of the rainflow matrix
A larger bin size has greaterprecision but will take longer to
solve and use more memory
Bin size defaults to 32, meaningthat the Rainflow Matrix is 32 x32 in dimension.
Non-constant amplitude, proportional loading
Bin size defines how many divisions the cyclecounting history should be organized into
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Non-constant amplitude, proportional loading
For Stress Life, another available option whenconducting a variable amplitude fatigue analysis isthe ability to set the value used for infinite life
In constant amplitude loading, if the alternatingstress is lower than the lowest alternating stress onthe fatigue curve, the fatigue tool will use the life atthe last point
This provides for an added level of safety becausemany materials do not exhibit an endurance limit
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Non-constant amplitude, non-proportionalloadingMost general case and is similar to Constant Amplitude,
non-proportional loading, but in this loading class thereare more than 2 different stress cases involved that
have no relation to one anotherNot only is the spatial location of critical fatigue life
unknown, but also unknown is what combination ofloads cause the most damage
Thus, more advanced cycle counting is required suchas path independent peak methods or multiaxial criticalplane methods
Currently the ANSYS Fatigue Module does not supportthis type of fatigue loading
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Mean Stress Correction
Cyclic fatigue properties of a material are oftenobtained from completely reversed, constantamplitude tests
Actual components seldom experience thispure type of loading, since some mean stress isusually present
If the loading is other than fully reversed, amean stress exists and may be accounted for
by using a Mean Stress Correction
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Mean Stress Correction (Stress Life)
SoderburgGoodman
Gerber
Mean Stress Curves
Mean Stress Dependent
Multiple r-ratio curvesNo Mean Stress Correction (None)
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Soderberg Is usually overly
conservative
Soderberg theory is notbounded when usingnegative mean stresses
ANSYS Fatigue Moduledoes bound the negativemeans stresses
Negative mean stress is
capped to the yield stress
1
__
=+
SS StrengthYield
Mean
LimitEndurance
gAlternatin
Mean Stress Correction (Stress Life)
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Goodman Most experimental datafalls between Goodmanand Gerber theories
Goodman theory isusually a good choicefor brittle materials
Goodman theory is notbounded when usingnegative mean stresses
ANSYS Fatigue Module
does bound the negativemeans stresses to theultimate stress
Mean Stress Correction (Stress Life)
1
__
=+
SS StrengthUltimate
Mean
LimitEndurance
gAlternatin
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Gerber Most experimental datafalls between Goodmanand Gerber theories
Gerber theory usually agood choice for ductilematerials
Gerber theory isbounded when usingnegative mean stresses
Mean Stress Correction (Stress Life)
1
2
__
=
+
SS StrengthUltimateMean
LimitEndurance
gAlternatin
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Mean Stress Curves Uses experimentalfatigue data to accountfor mean stress effects
Two Types AvailableMean Stress Dependent
Multiple r-ratio curves
In general, it is notadvisable to use anempirical mean stresstheory if multiple meanstress data exists
Mean Stress Correction (Stress Life)
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Morrows method Modified Elastic term in
the strain-life equation
Consistent with
observations that meanstress:
is significant at lowvalues of plastic strain
has little effect at highvalues of plastic strain
Incorrectly predicts thatthe ratio of elastic toplastic strain isdependent on meanstress
Mean Stress Correction (Strain Life)
( ) ( )cff
b
f
Meanf
NN
E
22'
'
2
+
=
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Smith, Watson andTopper (SWT)
Use a different equationto account for the
presence of meanstresses
It has the limitation that itis undefined for negative
maximum stressesThe physical
interpretation of this isthat no fatigue damage
occurs unless tension ispresent at some pointduring the loading
Mean Stress Correction (Strain Life)
( )( ) ( ) cb
f
f
b
f
f
Maximum NNE
f+
+=
22'
2
'2
2'
'
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Multiaxial Stress CorrectionExperimental test data is mostly uniaxial whereas FE
results are usually multiaxialAt some point, stress must be converted from a
multiaxial stress state to a uniaxial one
In the ANSYS Fatigue Module: Von-Mises, max shear, maximum principal stress, or any of the
component stresses can be used to compare against theexperimental uniaxial stress value
A signed Von-Mises stress may be chosen where the Von-Mises stress takes the sign of the largest absolute principalstress
This is useful to identify any compressive mean stresses since
several of the mean stress theories treat positive and negativemean stresses differently.
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Fatigue Modifications
Value of Infinite LifeFatigue Strength Factor
Loading Scale Factor
Interpolation Type (Stress Life)
Log-log
Semi-log Linear
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Value of Infinite Life (Stress Life) In constant amplitude loading, if the alternating stress is
lower than the lowest alternating stress on the fatigue curve,the fatigue tool will use the life at the last point
This provides for an added level of safety because manymaterials do not exhibit an endurance limit
However, in non-constant amplitude loading, cycles with very
small alternating stresses may be present and may incorrectlypredict too much damage if the number of the small stresscycles is high enough
To help control this, the user can set the infinite life value thatwill be used if the alternating stress is beyond the limit of the
SN curve Setting a higher value will make small stress cycles less
damaging if they occur many times The rainflow and damage matrix results can be helpful in
determining the effects of small stress cycles in your loadinghistory
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Rainflow matrix for a
given load history.
Resulting Damage Matrix
when the Value of InfiniteLife is equal to 106 cycles.
Total damage is
calculated to be 0.19.
Resulting Damage
Matrix with when the
Value of Infinite Lifeis equal to 109 cycles.
Total damage is
calculated to be 0.12
(37% less damage).
Fatigue Analysis in Workbench
Value of Infinite Life (Stress Life)
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Fatigue Strength FactorModification factors to account for the differences
between the in service part from the as testedconditions
In design handbooks, the fatigue alternating stress
is usually divided by this modification factor In the ANSYS Fatigue Module, the Fatigue Strength
Factor (Kf) reduces the fatigue strength and mustbe less than one
Note that this factor is applied to the alternating stressonly
Does not affect the mean stress.
Same as values from Handbooks (Example: Shigley) butall factors combined into one value
factorscaleloadneededgaugestrain200
loadFEM1
gaugestrain200
1000
1000
loadFEM1=
=
lbs
lbs
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Loading Scale FactorLoading Scale Factor that will scale all stresses,
both alternating and mean by the specified valueThis value may be parameterized
Applying a scale factor is useful to avoid having to
solve the static model again to see the effects ofchanging the magnitude of the FEM loads
In addition, this factor may be useful to convert a
non-constant amplitude load history data into theappropriate values
Example:
gaugestrain200gaugestrain2001000 lbs
FactorScaleLoadNeededgaugestrain200
loadFEM1
gaugestrain200
1000
1000
loadFEM1
=
=
lbs
lbs
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Interpolation Type (Stress Life)
When the stress life analysis needs to query the S-N curve, almost assuredly the data will not beavailable at the same stress point as the analysishas produced; hence the stress life analysis needs
to interpolate the S-N curve to find an appropriatevalue
Three interpolations are available
Log-log Semi-log
Linear
Results will vary due to the interpolation methodused
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Fatigue Results Calculations and results can be dependent upon the
type of fatigue analysis Results that are common to both types of fatigue
analyses are listed below:
Fatigue Life
Fatigue Damage at a specified design life Fatigue Factor of Safety at a specified design life
Stress Biaxiality
Fatigue Sensitivity Chart
Rainflow Matrix output (Beta for Strain Life at 10.0) Damage Matrix output (Beta for Strain Life at 10.0)
Results that are only available for Stress Life are:
Equivalent Alternating Stress
Results that are only available for Strain Life are: Hysteresis
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Fatigue life Shows the available life for the given fatigue analysis
Result contour plot, which can be over the whole model orscoped
This, and any contour result, may be exported to a tab-delimitedtext file by a right mouse button click on the result
If loading is of constant amplitude, this represents the numberof cycles until the part will fail due to fatigue
If loading is non-constant (i.e. a load history), this representsthe number of loading blocks until failure
If a given load history represents one hour of loading and the lifewas found to be 24,000, then the expected model life would be1,000 days
In a Stress Life analysis with constant amplitude, if theequivalent alternating stress is lower than the lowest
alternating stress defined in the S-N curve, the life at thatpoint will be used.
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Fatigue
Life
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Fatigue Damage at a Design Life
Fatigue damage is defined as the design lifedivided by the available life
This result may be scoped
The default design life may be set throughthe Control Panel
For Fatigue Damage, values greater than 1indicate failure before the design life isreached
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Fatigue
Damage
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Fatigue Factor of Safety at a Design Life
Contour plot of the factor of safety withrespect to a fatigue failure at a given designlife
Maximum Factor of Safety displayed is 15Like damage and life, this result may be
scoped
For Fatigue Safety Factor, values less thanone indicate failure before the design life
has been reached
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Fatigue
FactorofSafety
at aDesign
Life
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Stress Biaxiality IndicationFatigue material properties are typically based on
uniaxial stressesReal world stress states are usually multiaxialThis fatigue result gives the user some indication of
the stress state over the model and how to interpret
the resultsBiaxiality indication is defined as the smaller in
magnitude principal stress divided by the largerprincipal stress with the principal stress nearestzero ignored
Stress Biaxiality Indication Values: Biaxiality of zero corresponds to uniaxial stress
Biaxiality of 1 corresponds to pure shear Biaxiality of 1 corresponds to a pure biaxial state
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Stress Biaxiality Indication
Majority of this model is under a pure uniaxial stress, withparts exhibiting both pure shear and nearly pure biaxiality
Comparing biaxiality with safety factor, the most damagedpoint occurs at a point of nearly uniaxial stress
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Stress Biaxiality Indication
In the preceding example, if the mostdamaged spot was under pure shear, then itwould be desirable to use S-N data
collected through torsional loading, if suchdata was available
Unfortunately, collecting experimental data
under different loading conditions is costprohibitive and not often done
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Stress Biaxiality IndicationFor non-proportional fatigue loading, there
are multiple stress states and thus there isno single stress biaxiality at each node The user may select either to view the average or
standard deviation of stress biaxiality
The average value may be interpreted as aboveand in combination with the standard deviation,the user can get a measure of how the stressstate changes at a given location
Thus a small standard deviation indicates a
condition where the loading is near proportionalwhile a larger deviation indicates change in thedirection of the principal stress vectors
This information can be used to give the useradditional confidence in his results or whethermore in depth fatigue analysis is needed toaccount for non-proportionality
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Fatigue Sensitivity Chart
Shows how the fatigue results change withloading at the critical location on the model
User specifies:
Sensitivity for life, damage, or factorof safety
Number of fill points
Load variation limitsNegative variations are allowed to see
the effects of a possible negative meanstress if the loading is not totally
reversedLinear, Log-X, Log-Y, or Log-Log scaling
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FatigueSensitivityChart
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Rainflow Matrix Output (Beta, Strain Life, 10.0)
Shows the rainflow matrix at the critical location
Only applicable for non-constant amplitude loadingwhere rainflow counting is needed
This result may be scoped
3-D histogram where alternating and mean stress isdivided into bins and plotted
Z-axis corresponds to the number of counts for a givenalternating and mean stress bin
This result gives the user a measure of the composition ofa loading history
Such as if most of the alternating stress cycles occur at anegative mean stress
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Fatigue Analysis in Workbench
Rainflow
MatrixOutput(Beta,
StrainLife,
10.0)
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Fatigue Analysis in Workbench
Damage Matrix Output (Beta for Strain Life at 10.0) Shows the damage matrix at the critical location on the model
This result is only applicable for non-constant amplitudeloading where rainflow counting is needed
This result may be scoped
3-D histogram where alternating and mean stress is divided
into bins and plotted Z-axis corresponds to the percent damage that each of the
Rainflow bins cause
Similar to the rainflow matrix except that the percent damage thateach of the Rainflow bins cause is plotted on the Z-axis Thisresult gives the user a measure of the composition of what iscausing the most damage
Such as if most of the counts occur at the lower stressamplitudes, but most of the damage occurs at the higher stress
amplitudes
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Fatigue Analysis in Workbench
Damage
MatrixOutput(Beta
forStrain
Life at10.0)
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Fatigue Analysis in Workbench
Damage MatrixRainflow Matrix
In this particular case although most of the counts
occur at the lower stress amplitudes, most of thedamage occurs at the higher stress amplitudes
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Fatigue Analysis in Workbench
Equivalent Alternating Stress (Stress LifeOnly)
Stress Life always needs to query an SN curve torelate the fatigue life to the stress stateEquivalent alternating stress is the stress used to
query the fatigue SN curve after accounting for
fatigue loading type, mean stress effects, multiaxialeffects, and any other factors in the fatigue analysis
Equivalent alternating stress is the last calculatedquantity before determining the fatigue life
This result is not applicable to Stress life with non-constant amplitude fatigue loading due to the factmultiple SN queries per location are required andthus no single equivalent alternating stress exists
This result is not applicable to Strain Life
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Fatigue Analysis in Workbench
Equivalent Alternating Stress (Stress Life
Only)The usefulness of this result is that in general it
contains all of the fatigue related calculations
independent of any fatigue material properties Note that some mean stress theories use static
material properties such as tensile strength so
Equivalent Alternating Stress may not be totallydevoid of material properties
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Fatigue Analysis in Workbench
Equivalent Alternating Stress (Stress Life Only)Equivalent Alternating Stress may be useful in a
variety of situations: Instead of possible security issues with proprietary material
stress life properties, an engineer may be given anequivalent alternating stress design criteria.
The equivalent alternating stress may be exported to a 3rdparty or in house fatigue code that performs specializedfatigue calculations based on the industry specificknowledge.
An engineer can perform a comparative analysis among avariety of designs using a result type (stress) that he may feelmore comfortable with.
A part can be geometrically optimized with respect to fatigue
without regard to the specific material or finishing operationsthat are going to be used for the final product
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Fatigue Analysis in Workbench
EquivalentAlternatingStress(Stress Life
Only)
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Fatigue Analysis in Workbench
Hysteresis Result for Strain Life The Hysteresis result plots the local elastic-plastic response
at the critical location In strain-life fatigue, although the finite element response maybe linear, the local elastic/plastic response may not be linear
The Neuber correction is used to determine the local
elastic/plastic response given a linear elastic input Repeated loading will form closed hysteresis loops as a resultof this nonlinear local response
Constant amplitude analysis a single hysteresis loop is created
Non-constant amplitude analysis numerous loops may becreated via rainflow counting
This result may be scoped
Hysteresis helps you understand the true local response
which may not be easy to infer
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Fatigue Analysis in Workbench
Hysteresis
Result forStrain Life
W ki ith L M d l
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Working with Legacy Models
Question:
What if you have a legacy model andwish to perform a Fatigue Analysis?
Answer:
FE Modeler
Working with Legacy Models
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g g yInitial Mesh in FE Modeler
Working with Legacy Models
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g g yInitial Configuration in FE Modeler
Working with Legacy Models
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g g yTransfer to Design Simulation
Working with Legacy Models
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g g yDesign Simulation Results
Optimization with Fatigue
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Optimization with Fatigue
Question:
What if you have a legacy model andwish to optimize the Fatigue Life?
Answer:
FE Modeler, ANSYS Mesh Morpher andANSYS DesignXplorer
Optimization with Fatigue
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p gANSYS Mesh Morpher Parametric Geometry
Thickness increase
Diameter decrease
Optimization with Fatigue
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p gDesign Simulation Results Stress Variations
Optimization with Fatigue
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p gParameterize Fatigue Life then DX!
Fatigue Within Workbench Fits Into
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gEveryones Process
Insert aFatigue
Tool
Make
FatigueDecisions
Fatigue Within Workbench Fits Into
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Everyones Process
Inset in
FatigueResults
Life
Factor ofSafety
Solve
Fatigue Within Workbench Fits Into
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Everyones Process
Review
FatigueResults
Life
Factor ofSafety
Fatigue Within Workbench Fits Into
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Everyones Process
Insert a Fatigue Tool 2 Clicks
Make Fatigue Decisions - Varies
Inset in Fatigue Results - Life 2 Clicks
Factor of Safety 2 Clicks
Solve 1 Click
Review Fatigue Results
Life 1 Click
Factor of Safety 1 Click
Adding a Fatigue Analysis requires as little as sixMouse Clicks!!!!
Fatigue Within Workbench Fits Into Everyones Process!!!!
Predicting Fatigue Life with ANSYS
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Workbench
Questions?
Ray Browell, P. E.
ANSYS, Inc.(724) 514-3070
mailto:[email protected]:[email protected]