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Rectangular pulse train
Posted May 21, 2012, 1:35 a.m. EDT Heat Transfer & Phase Change Version 4.2 1 Reply
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hi Ivar ,
i know this topic has been discussed on this forum but i still have a problem.
i want to generate a rectangular pulse train of pulse width = 28e-9 , frequency = 1 Hz
i used the rect function along with mod function to get an analytic function an1= rect1(mod(t[1/s],1e-9))
but when i plot this for time t = 0 to 1 sec i get zero magnitude , after solving i also found out that heat flux is zero throughout the time . I also tried 'make periodic' option but still not getting the plot.
As discussed earlier on some other thread , i made sure that the solver is selected as strict but still no luck .
i have to model 2 pulses each of 28 ns width in every second (t = 0 to 2 sec ) please help me with this .
Hirendra
i know this topic has been discussed on this forum but i still have a problem.
i want to generate a rectangular pulse train of pulse width = 28e-9 , frequency = 1 Hz
i used the rect function along with mod function to get an analytic function an1= rect1(mod(t[1/s],1e-9))
but when i plot this for time t = 0 to 1 sec i get zero magnitude , after solving i also found out that heat flux is zero throughout the time . I also tried 'make periodic' option but still not getting the plot.
As discussed earlier on some other thread , i made sure that the solver is selected as strict but still no luck .
i have to model 2 pulses each of 28 ns width in every second (t = 0 to 2 sec ) please help me with this .
Hirendra
1 Reply Last Post May 21, 2012, 4:50 a.m. EDT
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Posted:
1 decade ago
Hi
indeed its difficlt to see exactly what is pahhening, as the self scaling of the plots play you a game here
you can aleways combine a rect with a mod(t[1/s],1) see images
Do not forget to carefully define the time sequence and use strict and not free time stepping
I suspect the ration 1e-9 to 1 is too large for the analytical function, try asking "support"
--
Good luck
Ivar
indeed its difficlt to see exactly what is pahhening, as the self scaling of the plots play you a game here
you can aleways combine a rect with a mod(t[1/s],1) see images
Do not forget to carefully define the time sequence and use strict and not free time stepping
I suspect the ration 1e-9 to 1 is too large for the analytical function, try asking "support"
--
Good luck
Ivar
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