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lunar1984 October 29, 2013 16:14

phi-T plot
1 Attachment(s)
Hi All,

I am currently conducting diesel cycle simulation with STAR-CD 4.16. I am wondering if it is possible to get phi-T plot which can explain the soot and NOx formation. The example of phi-T plot is attached.

Thank you in advance.

lunar1984 November 7, 2013 10:37

Does anyone have an idea about it? Still waiting for the solution.


pmrvignesh May 6, 2014 09:59

Hi Jason,
In order to plot phi-T, you need to calculate phi. phi= equivalence ratio= Mass.fraction of fuel/Mass.fraction of air(oxidizer).

Your CFD calculations would have yielded the mass fraction of fuel and oxidizer, in all the cells. You can then use those values to calculate phi, and then plot against temperature values.

ok_computer May 19, 2014 06:25


one thing is also how you calculate Lambda or Phi. This should be calculated so that it is based on the mixture fraction e.g. from

Lambda = (m_fu_st(1-f))/f(m_o2_st+m_n2_st)

where f is mixture fraction and m_fu_st is the stoichiometric fuel mass.

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