Change of boundary condition value (mole fraction) of species after convergence

- February 6, 2021 at 11:08 am
  
  Anshul
  Subscriber
  
  Hi all,nI am simulating a reforming reaction in 2D-axisymmetric case. While putting velocity inlet condition, I am specifying the concentration of inlet species. Say for example. 0.47 for methanol. But as I run the simulation, and get convergence ( less than 10e-05), it seems that the boundary condition of species is changed.nHow this is possible as boundary condition should remain same as given by user. I also monitor the mole fraction of methanol while running calculation, it seems to drop sudden at start from 0.47 to 0.29 etc..nHowever, if I increased the inlet velocity then this change is decreasing. I am not understanding why this is happening?nAlso, for pressure outlet condition, I have put 0 value for the species. Is it happening due to reverse flow?nPlease help me with this.nnAnshuln
- February 8, 2021 at 12:05 pm
  
  Rob
  Ansys Employee
  
  The boundary condition should be respected, and if you do a surface report what do you see? Similarly plot volume fraction on the inlet only with node values off and local range. n

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