Challenge on Combustion
Combustion stimulation:
Geometry:
The sectioned view of combustor model is shown here.
In this geometry in order to use a refined mesh the geometry is cut to quatre its size and and plane is taken out for the CFD stimulation. In this plane the parts are combined together.
2D geometry:
Mesh:
The prepared geometry is made to have a refined mesh and procximity in faces and edges for accurate stimulation.
Setup:
The regular steady state, pressure based stimulation with k-epsilon as turbulance model is done with following species model:
Then the nox and soot model is selected according the given condition. Then hybrid initialisation is done and calculated till it reach convergence.
Results:
Line plots locations:
Temperature:
Velocity:
Mass faction of CH4:
Mass faction of CO:
Mass faction of CO2:
Mass faction of H2O:
Mass faction of N2:
Mass faction of O2:
Mass faction of NOx:
line graph:
Contour:
Mass faction of SOOT:
line graph:
Contour:
The water is added thorugh fuel inlet whose addition percentage is from 5% to 30% by mole. In fuel inlet there is one mole of CH4 that 100% of inlet with that as refernce addition of water is done from 5%,15%,25% and 30% with parametric study approach for further stimulation.
Parametric table:
for 5% of water:
Mass faction of NOx:
line graph:
Contour:
Mass faction of SOOT:
line graph:
Contour:
for 15% of water:
Mass faction of NOx:
line graph:
Contour:
Mass faction of SOOT:
line graph:
Contour:
for 25% of water:
Mass faction of NOx:
line graph:
Contour:
Mass faction of SOOT:
line graph:
Contour:
for 30% of water:
Mass faction of NOx:
line graph:
Contour:
Mass faction of SOOT:
line graph:
Contour:
Inference:
From the table in parametric table, line graph along tube and and the contour of the mass fraction of NOx and SOOT it is clearly seen that addition of water reduces the NOx and SOOT. Eventually outlet temperature is reduced due to addition of water. The reduction of Temperature, NOx and SOOT is proportional to addition of water in reaction. The reduction of pollutants emmission is reduced with the side effect of reduction of outlet temperature also. Considering the environtment one must choose the best proportion of addition of water with fuel with respect to the need of outlet temperature. Thus this clearly shows that the addition of water reduces the emmission of NOx and SOOT in the combustion equation of methane.