cuspaceflight / bamboo

Cooling system modelling for liquid rocket engines.
GNU Affero General Public License v3.0
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Changes in thermal expansion coefficients #24

Open hf360F opened 3 years ago

hf360F commented 3 years ago

Thermal expansion coefficients are usually given as an average value for a certain temperature range. In reality there are non-linearities over large ranges - the range of temperature differences we're working with is definitely large enough that this is a concern.

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If I can verify the expansion coefficient of alloys are not noticeably affected by the alloying elements, I'll see if I can implement polynomials for thermal expansion coefficients.

hf360F commented 3 years ago

Maybe it isn't worth the hassle - from 300 K to 1000 K the difference is only about 20%, so it might be easier to just use the 1000 K value for all temperatures as a worst case