Combustion Analysis
Combustion
Description:
Combustion is a reaction between fuel and oxygen.When fuel and air reacts it releases the heat and light energy.Heat and light energy result in the flame.In this case we are going to analyse the combustion inside the chamber and the temperature and mass fraction of the each components.
Possible types of combustion simulation in ansys fluent.
- Non Premixed Combustion.
- Premixed Combustion.
- Partially Mixed Combustion.
- Fluid Phase (voumetric reactions)
- Wall (Surface Reactions)
- Particles (Surface reactions)
- Porous Regions.
Steps in Combustion Simulation:
- Geometry
- Meshing
- Set up
- Solution
- Result
Geometry:
- Importing the solid model.
- Extracting the 2D model.
Importing the solid model:
The first step in this case is importing the solid model of the combustion chamber.
Extracting the 2D model:
The next step is to extract the 2D model from the 3D geometry.The 2D model is extracted by creating the planes along the three axis and splitting the body of the 3D model.After that the splitted body is copied and pasted into the another geometry and then combine tool is used to combine the fuel and air inlet.
Meshing:
The 2D model is discretized into a small elements of size 0.001m.
- No of elements=34612.
- No of nodes=17827.
Set up:
The set up for this case is as follows,
General :1.Pressure based solver
2.Steady state condition
3.Axis symmetric
Model :1.Energy-On
2.Viscous-K epsilon-Standard wall function
3.Species-Methane Air
Material :1.Mixture-(Methane,Carbondioxide,Oxygen,MethaneAir,Nitrogen,Watervapour).
2,Fluid-Air.
Cell zone condition :1.Surface-Fluid.
Boundary condition:1.Air inlet-Velocity 0.5m/s-Species (O2-0.23).
2.Fuel inlet-Velocity 80m/s-Species (CH4-1)
3.Outlet-Pressure outlet.
Initialization :Hybrid initialization
Solution:
The calculation is set to run for 700 iterations and it is converged in 250 iterations.
Result:
Temperature :
CO2 Mass Fraction:
H2O Mass Fraction:
N2 Mass Fraction:
CH4 Mass Fraction:
Conclusion:
In this case the temperature inside the combustion chamber is analysed and the four lines were created in equidistant and then the mass fraction for methane,carbon-di-oxide,nitrogen and water is analysed in the four lines.