Boundary Contitions/Mass fraction
 

Hey,
can someone help me please?

I had to simulate a combustion in a simple tube (diameter 25mm and length 500mm). Propane Air is used for the combustion.
I used a transient (0.2s time steps 0.002s) solution and a Eddy Disserpation Model and activated Eddy disserpation coefficient B=0.5

I think the problem is either in my boundary conditions or in the mass fraction.
But maybe sth else is wrong cause i never get a combustion

Boundary Conditions I tried were:
-Inlet at one end of the tube and the rest as a wall (free slip wall)
-Outlet at one end and the rest as a wall (the "in" wall is a hot free slip wall)
-Everything a wall (the "in" wall is a hot free slip wall)

My mass fractions are:
C3H8: 0.06
H20: 0.01
CO2:0.01
O2:0.232