Menu

Discussion Forum

New Discussion
查找

Discussion Closed This discussion was created more than 6 months ago and has been closed. To start a new discussion with a link back to this one, click here.

Step Function

Posted 2010年9月1日 GMT-4 10:59 Parameters, Variables, & Functions, Studies & Solvers Version 5.1 4 Replies

Pekir Joseph
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Hi:


I want to multiply a voltage source from the electrical interface by a step function to cause a delay, how to go about
that?

Thanks
4 Replies Last Post 2017年5月31日 GMT-4 10:24
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 1 decade ago 2010年9月1日 GMT-4 17:46
Hi

if I understand correctly your demand, I would propose to use the step function in V4 or a Heaviside (check the command.pdf doc) in V3.5 (they are the same in both versions, but they have been further implemented as clickable items in V4)
And then multiply your voltage amplitude by the step function, including a starting point (t-tau) and a rise time "DT" directly in the field where you need to define the voltage. (this applies to any variable by the way, not only to voltages)

--
Good luck
Ivar
Hi if I understand correctly your demand, I would propose to use the step function in V4 or a Heaviside (check the command.pdf doc) in V3.5 (they are the same in both versions, but they have been further implemented as clickable items in V4) And then multiply your voltage amplitude by the step function, including a starting point (t-tau) and a rise time "DT" directly in the field where you need to define the voltage. (this applies to any variable by the way, not only to voltages) -- Good luck Ivar
Amitabh Choudhury
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2015年4月10日 GMT-4 11:43
hi Ivar .. i want to apply lightning impulse voltage of 1.2/50 micro-sec to an electrode under electrostatics module ..plz suggest
hi Ivar .. i want to apply lightning impulse voltage of 1.2/50 micro-sec to an electrode under electrostatics module ..plz suggest
Daniel Connelly
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 10 years ago 2015年4月19日 GMT-4 15:51
Can you define it using ":?"? For example,

(t > 3) ? 1 : 0

would be a step going from 0 to 1 starting @ t = 3.
Can you define it using ":?"? For example, (t > 3) ? 1 : 0 would be a step going from 0 to 1 starting @ t = 3.
Sarizan Saaidon
Send Private Message Flag post as spam

Please login with a confirmed email address before reporting spam

Posted: 7 years ago 2017年5月31日 GMT-4 10:24

hi Ivar .. i want to apply lightning impulse voltage of 1.2/50 micro-sec to an electrode under electrostatics module ..plz suggest


Have you solve the problem?
[QUOTE] hi Ivar .. i want to apply lightning impulse voltage of 1.2/50 micro-sec to an electrode under electrostatics module ..plz suggest [/QUOTE] Have you solve the problem?

Note that while COMSOL employees may participate in the discussion forum, COMSOL® software users who are on-subscription should submit their questions via the Support Center for a more comprehensive response from the Technical Support team.

Suggested Content