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dbirch997 / cantera

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Emissivity coefficient #68

Closed GoogleCodeExporter closed 9 years ago

GoogleCodeExporter commented 9 years ago 
What steps will reproduce the problem?
1. A zero-D reactor computation with radiation heat flux
2. Put an emissivity between 0.0 and 1.0.

What is the expected output? What do you see instead?
The computed wall heat flux (and so the exhaust temperature of the reactor) 
should change with the value of the emissivity. 
Instead, the code understand that the emissivity coefficient equals 1.0 (for 
every value between 0.0 et 1.0). 

What version of the product are you using? On what operating system?
I'm using CANTERA 1.8 (last svn checkout) on Ubuntu 11.04.

Please provide any additional information below.
I took a look to the zeroD/Wall.cpp file. 
It seems that the emissivity coefficient (m_emiss) is used in order to access 
to the computation of the radiation heat flux. But the formula is :
q1 = m_area * StephanBoltz * (tl*tl*tl*tl - tr*tr*tr*tr)
The emissivity is not used. The radiation heat flux should be :
q1 = m_emiss * m_area * StephanBoltz * (tl*tl*tl*tl - tr*tr*tr*tr)

Am I right ?

Regards,

Pierre

Original issue reported on code.google.com by benard.p...@gmail.com on 21 Mar 2012 at 1:33

GoogleCodeExporter commented 9 years ago 
Fixed in r1326.

Original comment by yarmond on 23 Mar 2012 at 10:18