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Using a function as an input to simulate turn-on turn-off sequence
Posted 17 janv. 2014, 13:47 UTC−5 Heat Transfer & Phase Change Version 4.3 2 Replies
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I'm using the Joule Heating module and I'm modeling a simple wire heater that heats up when I run a current trough it. I want to see how the temperature of the heater decays as a function of time in order to see if it falls off exponentially and check that the simulation is correct. However to do this I have to run the current for a while and then turn it off. To simulate this I created a piecewise function whose value is 2mA from 0 to 5s and then it's 0mA from 5 to 10s. I used continuous 1st derivative with a transition zone size of 0.1.
In my terminal node I write the name of my piecewise function rather than a number and I run the simulation. I get the error:
Failed to evaluate variable Jacobian.
- Variable: myfunc
- Global scope
- Feature: Time-Dependent Solver 1 (sol2/t1)
What am I doing wrong? How do implement a function as input for the current to simulate turning off the current?
In my terminal node I write the name of my piecewise function rather than a number and I run the simulation. I get the error:
Failed to evaluate variable Jacobian.
- Variable: myfunc
- Global scope
- Feature: Time-Dependent Solver 1 (sol2/t1)
What am I doing wrong? How do implement a function as input for the current to simulate turning off the current?
2 Replies Last Post 21 janv. 2014, 09:19 UTC−5
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Posted:
1 decade ago
I always use flc2hs function. Try
I0 = 2[mA]
ts = 5[s]
I = I0*(flc2hs(t,0.01)-flc2hs(t-ts,0.01))
Wish this helps
Lasse
I0 = 2[mA]
ts = 5[s]
I = I0*(flc2hs(t,0.01)-flc2hs(t-ts,0.01))
Wish this helps
Lasse
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Posted:
1 decade ago
Hello,
You can use the piecewise function,
Use the second derivative it's better.
Don't rename the piecewise function
In the terminal tape: pw1(t[1/s])
pw1 is where you have define your current in function of time.
Best regards
Julien
You can use the piecewise function,
Use the second derivative it's better.
Don't rename the piecewise function
In the terminal tape: pw1(t[1/s])
pw1 is where you have define your current in function of time.
Best regards
Julien