Understanding dynamic analysis time step is difficult? Not anymore!!BeaconIndia / No Comments
Understanding dynamic analysis time step is difficult? Not anymore!!
• Run the frequency analysis
• Duration of analysis is determined by the inclusion of the sufficient peak response oscillations. The analysis duration is smaller for higher frequency response than low-frequency response oscillations are expected
For example, to include time step
If your frequency is fhighest= 100HZ
Time period, T=1/ fhighest = 1/100
Consider, the number of points on the amplitude as 10
Then, Time period /Step = 0.01/10 = 0.001
Let’s consider example in SolidWorks,
1. Run the frequency analysis and Highest natural frequency of fhighest 1556 Hz for 65th Mode Shape
Therefore, Time period =1/ fhighest = 1/1556
Considering The step of 10 yields,
= 6.42e-4 / 10
The frequency of highest mode shape in the analysis is fhighest 1556 Hz we including more than any other important frequency of load to satisfiy all time increment criteria if stress wave propagation is important.
For that we are considering a frequency of 2000Hz
Time increment =1/f = 1/2000
2. Calculating load time step.
In the same way time step is calculated for loading curve
t = 0.011/10
= 1.1e-3 sec
3. In dynamic analysis, large amount of data is saved on disc.
It is often recommended to save the data for specified solution of steps.
1st step = 5 e-5 / 0.011
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