I applied a heat source for 20 seconds then turned it off with a user defined function. I wanted to see my object cool. It does not cool. Idk why.
https://imgur.com/a/lnCtJh7
I have a 273 external temp and idealized radiation with emmisivity .75 set to all the boundary
https://imgur.com/a/AYleCPd
Even with external temp 200, no change
Thanks
Geometry not cooling?
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Re: Geometry not cooling?
If I start with a warm body using an initial condition, no body force, the body cools with time.
If I start with a cool body, it with a body force for a finite time until is is a warm body. Set heat source to 0, no cooling.
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Re: Geometry not cooling?
It appears I did not get it hot enough. If I heat the body well over the external boundaries then it cools.
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Re: Geometry not cooling?
If i start with a cold body the external boundary heats it.
If I heat the body some, then turn of the heat source the external boundary continues to heat it.
If I heat the body close to the boundary temperature, the boundary holds the body nearly constant.-
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Re: Geometry not cooling?
Oh it's cooling. It's just barely cooling -> -.001 K change per second when the ext. temp. is set to 100 K and the object is heated to 274 K. Surprising.
Thanks kevin
Thanks kevin
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Re: Geometry not cooling?
Hi
Typically whe this happens the user has forgotton to change the units of length to SI units. Your material parameters are in SI units. What is your system size looking in paraview?
Also, please don't use ".75", rather "0.75". Not everybody reads that correctly, I don't know about Elmer.
-Peter
Typically whe this happens the user has forgotton to change the units of length to SI units. Your material parameters are in SI units. What is your system size looking in paraview?
Also, please don't use ".75", rather "0.75". Not everybody reads that correctly, I don't know about Elmer.
-Peter
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Re: Geometry not cooling?
My block was 0.1 meter x 0.1 meter x 0.30 meter high.
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Re: Geometry not cooling?
Ok, seems plausible that a block of aluminum would radiate significantly in an hour or so. Maybe you could share the last vtu file from the time series. -Peter
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Re: Geometry not cooling?
@raback I believe all of my units are SI.
Do you think this sort of result is accurate/realistic to the simulation/model?
Are you suggesting I change something in ParaView? I don't understand.
Thanks
Do you think this sort of result is accurate/realistic to the simulation/model?
Are you suggesting I change something in ParaView? I don't understand.
Thanks
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Re: Geometry not cooling?
I believe he was responding to my post of 0.1 meter x 0.1 meter x 0.3 meter aluminum block.
We do not know the size or material of your block.
We do not know the size or material of your block.