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Heaviside function simulate Acoustic emission signal

Hello,

I need to apply a Heaviside function difference to simulate a Acoustic emission burst signal. Can help, how can I do this? What model should I use? I'm new working with COMSOL.

Thanks,

Nuno Gueiral

5 Replies Last Post Feb 4, 2013, 9:26 AM EST
Posted: 5 years ago Jan 30, 2013, 1:10 PM EST
Hi

the Heavyside functions of 3.5 are now readily available as Definitions - Functions : such as step, or rectangle or ramp ... , all with smoothing

--
Good luck
Ivar
Hi the Heavyside functions of 3.5 are now readily available as Definitions - Functions : such as step, or rectangle or ramp ... , all with smoothing -- Good luck Ivar

Posted: 5 years ago Jan 31, 2013, 12:45 PM EST
Hello,

I'm using de COMSOL 4.2a version.

Best regards,
Gueiral
Hello, I'm using de COMSOL 4.2a version. Best regards, Gueiral

Posted: 5 years ago Feb 1, 2013, 12:52 AM EST
Hi

in v4 look under Model - Definitions - Functions, and check the step, rect or ramp functions, these have Heavyside smoothing included

--
Good luck
Ivar
Hi in v4 look under Model - Definitions - Functions, and check the step, rect or ramp functions, these have Heavyside smoothing included -- Good luck Ivar

Posted: 5 years ago Feb 1, 2013, 5:07 PM EST
Hi

The ramp function worls perfectly fine, but if your lazy like me and u use the Heaviside function often, its easier to use COMSOL's inbuilt Heaviside function


flc1hs(X,scale)



Hi The ramp function worls perfectly fine, but if your lazy like me and u use the Heaviside function often, its easier to use COMSOL's inbuilt Heaviside function flc1hs(X,scale)

Posted: 5 years ago Feb 4, 2013, 9:26 AM EST
Hello,

Tank you Stevie for your answer.
I need to insert in COMSOL a function or a expression like this:
f is a impact force
f = F_max [flch2(t,t_rise )-flch2(t-t_width ,t_fall )]
where
F=max( F )/ S_max ( N / m 2 )
and
S_max=pi*(2.5e-3/2)^2

F : maximum force (2-5N)

and I don't know how? Could you help me?

Best Regards

Nuno
Hello, Tank you Stevie for your answer. I need to insert in COMSOL a function or a expression like this: f is a impact force f = F_max [flch2(t,t_rise )-flch2(t-t_width ,t_fall )] where F=max( F )/ S_max ( N / m 2 ) and S_max=pi*(2.5e-3/2)^2 F : maximum force (2-5N) and I don't know how? Could you help me? Best Regards Nuno

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