Somat eDAQlite - Page 144

Somat eDAQ lite
144
I2773-4.4 en
NOTE
Existing material databases may be defined in terms of either reversals to failure
(2
N
f
), load amplitude ( P /2) or stress amplitude ( S /2). Convert to the required
parameters as necessary.
Edit Model Parameters
Depending on the model selected, several parameters used in the computation are
available for modification by clicking the Edit Model Parameters button. The following
table lists the available model parameters and their corresponding variables in each
damage model.
NOTE
TCE accumulates no damage if the applied load or stress range is less than the fatigue
limit parameter.
Hysteresis
Specify the desired hysteresis level for the peak valley processing algorithm.
Damage Units
Select the desired output channel damage units. The available units are damage,
percent life or microdamage. Note that the output channel full-scale estimates are
automatically assigned based on this selection.
Window Samples
Specify the number of input samples used to generate one output sample. This sets
the analysis window size and associated output sample rate. Specify any positive
integer value greater than one.
NOTE
There can be some fairly significant computational overhead in generating each output
sample, particularly when the residual peak-valley sequence is relatively long (i.e., 100
residual peak-valleys or more). Consider this fact when setting the window samples
parameter.
Parameter Load-Life Stress-Life Strain-Life
Elastic modulus - - E
Fatigue strength coefficient P
o
S
o
S
f
’
Fatigue strength exponent bbb
Fatigue ductility coefficient - - e
f
’
Fatigue ductility exponent - - c
Fatigue limit load limit stress limit -
HBM: public