Radioisotope concentration in convective flow

Rimidalv · July 6, 2010, 05:18

Hi everyone!

I have been trying to calculate the steady-state concentration of the radioactive isotope of nitrogen N-16 in the coolant of a pool type experimental reactor. The isotope is created by the absorption of a neutron in O-16 and a subsequent emission of a proton.

The reaction takes place in proximity of the reactor core, the nitrogen is then carried around by the convective flow and decays with time.

I have created an additional variable and so far managed to simulate its transport by the fluid.
How could I specify the decay term (of the form -lambda*c, where c is the concentration of the isotope) in the transport equation?

Thank you!

Rimidalv

ghorrocks · July 6, 2010, 19:50

Hopefully a source term can do this. With luck you can apply the source term across the whole domain.

Rimidalv · July 8, 2010, 08:05

Hi again!

I think I got the problem solved. I did not know that a subdomain in the fluid has to be created, in which a source term can be specified.
I am currently running the simulation and will let you know whether it has worked.

Thank you for the suggestion!

Rimidalv

July 6, 2010, 05:18	Radioisotope concentration in convective flow	#1
Rimidalv New Member Vladimir Radulovic Join Date: Jul 2010 Posts: 2 Rep Power: 0	Hi everyone! I have been trying to calculate the steady-state concentration of the radioactive isotope of nitrogen N-16 in the coolant of a pool type experimental reactor. The isotope is created by the absorption of a neutron in O-16 and a subsequent emission of a proton. The reaction takes place in proximity of the reactor core, the nitrogen is then carried around by the convective flow and decays with time. I have created an additional variable and so far managed to simulate its transport by the fluid. How could I specify the decay term (of the form -lambda*c, where c is the concentration of the isotope) in the transport equation? Thank you! Rimidalv ramakant likes this.

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July 6, 2010, 19:50		#2
ghorrocks Super Moderator Glenn Horrocks Join Date: Mar 2009 Location: Sydney, Australia Posts: 17,870 Rep Power: 144	Hopefully a source term can do this. With luck you can apply the source term across the whole domain.

July 8, 2010, 08:05		#3
Rimidalv New Member Vladimir Radulovic Join Date: Jul 2010 Posts: 2 Rep Power: 0	Hi again! I think I got the problem solved. I did not know that a subdomain in the fluid has to be created, in which a source term can be specified. I am currently running the simulation and will let you know whether it has worked. Thank you for the suggestion! Rimidalv