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Mixing of two fluids at different temperatures

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Hello

This is the scenario that I am attempting to capture:

You have a box with a divider in the middle. On one side is water at one temperature. On the other side is water at a different temperature. At time zero, you quickly raise the divider so that the fluids are able to mix. I have set this up by using an initial condition for the temperature that includes a step function at the location of the divider.

However, I always get the error: Failed to find consistent initial values. Last time step is not converged.

I assume this is because the initial conditions are not physically possible, perhaps because I left the initial pressures at 0.

I have attached my file. Please note that this is supposed to mimic a microfluidic device, so the length scale is very small (centimetres).

0 Replies Last Post Mar 25, 2015, 1:00 p.m. EDT
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Hello Adam Mepham

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