[simoncic]

Hi Hugo,
but how can FixedConstraint and LinearMovementConstraint go together? First set derivative in time to zero – i.e. require constant temperature, but second require linear evolution in time, so the derivative in time is constant.

By constraining partial derivatives I thought of a model, where I have a heat flux (heat power divided by surface area) over some surface. A very simplistic example would be some inflamed region inside the normal tissue that generates some known heat power/flux. I would like to evaluate stationary temperature spatial distribution in normal tissue. In the simplest scenario I would assume some constant temperature outside the normal tissue, constant flux on the border between inflamed region and normal tissue and I would evaluate stationary state by simulating state after long time. For modeling constant flux through the surface I think I have to constrain partial derivative on the surface. Is that doable and right way to go?

[simoncic]

OK, things are becoming more clear 🙂

I am still wondering why this example has these two lines:
<FixedConstraint indices=”@../box-cold.indices” />
<LinearMovementConstraint template=”Vec1d” keyTimes=”0 0.005 0.006″ movements=”0 0 1″ indices=”@../box-cold.indices” />

To my understanding, first line fix temperature to some value (zero?) for nodes in cold box, while next line set linear change of the temperature for the same nodes. Doesn’t second line override first line?

Is LinearMovementConstraint really linear? I.e. the temperature varies linearly (linear interpolation) between two nearby predefined points? Or is it piecewise constant (at predefined point is set to some value and kept constant until next point)?

I am also interested if it is possible to constrain partial derivative of the temperature in the direction of the surface; i.e. thermal flux.

[simoncic]

Thanks!

[simoncic]

Thank you for the answer. So basically “ForceField” defines partial equation to be solved? Are then these tags ever inportant?

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