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Moving laser

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I'm a simulation a moving laser though a zinc pill, the problem is that i can't move the surface with the heat flux, the thing is that if i use a Parametric sweep Comsol will compute one point and ignore the other ones, like doing 1 study with each point of the laser and not a complete line. The other thing that i've been trying is to change the position of the circle with heat flux but i can't do this because it only accepts parameters an they can't depend of time or any other variable.

If someone can help me please...

Thanks

4 Replies Last Post Nov 14, 2012, 7:46 a.m. EST
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Nov 5, 2012, 4:48 p.m. EST
Hi

I'm not sure I undestand you correctly, but if you run a motion defined by "t" and you have a transient solver, you will anyhow only have a point per time step, and never any true "line", up to you to define "small" time steps to mimic more or less a line, and force the solver to "strict stepping" and not the default "automatic" to keep it making small steps. With the drawback that it takes some time to solver for all steps ...

--
Good luck
Ivar
Hi I'm not sure I undestand you correctly, but if you run a motion defined by "t" and you have a transient solver, you will anyhow only have a point per time step, and never any true "line", up to you to define "small" time steps to mimic more or less a line, and force the solver to "strict stepping" and not the default "automatic" to keep it making small steps. With the drawback that it takes some time to solver for all steps ... -- Good luck Ivar

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Posted: 1 decade ago Nov 5, 2012, 4:55 p.m. EST
Sir, thanks for your repply i was waiting for it. THe problem is that i want to translate a circle not a single point (the heat is beeing "produced" in the whole circle), and in the circle position i can't define a function like this.

X= 0.007+ 0.001*t
Y= 0.004-0.002*t

Problem is that i need a moving heat flux though all the surface.

Thanks

Sir, thanks for your repply i was waiting for it. THe problem is that i want to translate a circle not a single point (the heat is beeing "produced" in the whole circle), and in the circle position i can't define a function like this. X= 0.007+ 0.001*t Y= 0.004-0.002*t Problem is that i need a moving heat flux though all the surface. Thanks

Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago Nov 6, 2012, 12:34 a.m. EST
Hi

if you want to loop in a circle, the easiest is to define a cylindrical coordinate and refer to that one, and set the time variable in phi, or to use a x0+x1*sin(2*pi*freq*t) y0+y1*cos(2*pi*freq*t) type motion

--
Good luck
Ivar
Hi if you want to loop in a circle, the easiest is to define a cylindrical coordinate and refer to that one, and set the time variable in phi, or to use a x0+x1*sin(2*pi*freq*t) y0+y1*cos(2*pi*freq*t) type motion -- Good luck Ivar

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Posted: 1 decade ago Nov 14, 2012, 7:46 a.m. EST
Hi,

Have you tried to discretize your circle of laser (in t1 seconds, for example) in X parts by changing your geometry?
Each one corresponds to one pulse of t1/X (s) width. Try to use the step function with a such delay to set the laser circle on boundary conditions.


Good luck

Dinh
Hi, Have you tried to discretize your circle of laser (in t1 seconds, for example) in X parts by changing your geometry? Each one corresponds to one pulse of t1/X (s) width. Try to use the step function with a such delay to set the laser circle on boundary conditions. Good luck Dinh

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