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prescribed displacement/frequency domain study
Posted Jan 20, 2024, 3:54 p.m. EST Studies & Solvers, Structural Mechanics, Physics Interfaces Version 6.1 6 Replies
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im doing a 3d beam that have a prescribed displacement in the z direction but I needed to be with respect to time using this function below 200sin(120pi*t)[um] how do it add it on comsol
also how do i do a frequency domain study because it giving me a error that t is not defined.
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Start out with a frequency domain study (steady-state). Your frequency is seemingly 60 Hz, so that is what you input. Then go to a time-domain study.
-------------------René Christensen, PhD
Acculution ApS
www.acculution.com
info@acculution.com
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that correct my frequency is 60 Hz so i need to do a
- frequency domain, then using the result use
- frequency to time domain as the next step?
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Frequency dependent gets you the sinusoidal steady state solution.
Time dependent with sin(wt) gets you the initial transient when the sinusoidal excitation is turned on at t = 0.
Which one do you want??
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when t = 0
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OK if you are doing a time-dependent study then t is automatically time and the driving function should be written 200[um]sin(2pi60[1/s]t).
(If you do a frequency dependent study all quantities are phasors and time does not explicitly appear.)
(The website seems to remove asterisks from equations so you need to put them where they belong).
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A comment on the formatting: The forum uses the 'Markdown' syntax. Asterisk then means italic. If you want the asterisk to be shown as is, put a backslash ( \ ) in front of it. For more details, see https://www.comsol.com/forum/formatting-guide
The expression should then look like 200[um]*sin(2*pi*60[1/s]*t).
Entered as
200[um]\*sin(2\*pi\*60[1/s]\*t)
Henrik Sönnerlind
COMSOL