Week 10 - Simulating Combustion of Natural Gas.

Combustion:

Thermal NOx

Thermal is produced during the combustion process when nitrogen and oxygen are present at elevated temperatures.

Prompt NOx

Prompt NOx is formed from molecular nitrogen in the air combining with fuel in fuel-rich conditions which exist, to some extent, in all combustion

Aim:

To Perform a combustion simulation on the combustor model and plot the variation of the mass fraction of the different species’ in the simulation using line probes at different locations of the combustor . You need to plot for CO2, H2O, CH4, N2, O2, NOx emissions & Soot formation.

Geometry Simplification:

Mesh Settings:

Solver Settings:

Boundary Conditions:

Air Inlet

Fuel Inlet

Contour Plots:

Mass Fraction of CO2, H2O, CH4, N2, O2, NOx emissions & Soot formation

CH4

CO2

H20

O2:

N2

NOx emissions

Soot formation

Adding the water content in the fuel from 5% to 30% by mole

With 5% of water content

With 10% of water content

With 15% of water content

With 20% of water content

With 25% of water content

Parametric Study Chart

Conclusion:

It is been observed that addition of water into the fuel reduces the concentration of soot and nitrogen oxide in the combustor model...As it can be seen with 25% of added water the concentration of soot and nox is less compared to other cases.Furthermore temperature at the outlet of the model also reduces.