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Results and Discussion

You may receive a warning that says "The initial time increment may be too large for this problem. Check results carefully." . Our initial time step is set to 36seconds, which is rather large for transient analysis. The warning can be eliminated by turning off Auto Time Stepping under Analysis Settings and manually specify the initial time step.

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We will now examine the radiation heat transfer between the surface of the shell and the specimen. Click on Radiation shell under the solution tree and expand the Tabular Data, located in the lower right corner.

Tabular data of the shell

Tabular data of the specimen

The positive sign indicates heat is being transferred to the surrounding through radiation and the negative sign indicates heat is being absorbed from the surrounding. Because the specimen is so cold compared to the shell, some radiation emitted by the shell is absorbed and stored within the specimen. The specimen emits a very small amount of radiation because its initial temperature is near absolute zero but its emitted radiation gradually increases as the specimen gets warmer with time.

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