Modeling of Non-premixed Methane BERL Combustor through CFD Approach using ANSYS

Published on 04 Mar 2021. Written by Aman Singh

{ BERL- Burner Engineering Research Laboratory }

In the case of non-premixed methane BERL combustor, there are two ports incorporated: 

• one is for swirling combustion of air and 
• other for fuel inlet. 

Read more..

SLNOTE
It is an untagged burner, with swirl stabilization and swirl combustor which is stabilized due to the presence of central and outer circulation zones. 

Once the air and fuel are sent to the burner, the flame diffusion burning is seen inside the burner. The combustion occurs at the interface. 

Coming to Non-premixed combustion, the important thing is turbulent mixing as it distributes the gas evenly and also changes the 

• Density, 
• Temperature, 
• molar mass and 
• heat capacity. 

To understand the turbulent field, it is necessary to have an accurate prediction of the turbulent velocity field and by knowing about Mixture fraction. 

SLLATEST
The mixture fraction can be calculated by using the formula

F= (????i−????i,ox )/(????i,fuel −????i,ox)

Where

• ???????? is the elemental mass fraction for the element I,
• ????????,???????? is the value at the oxidizer stream inlet 
• ????????,???????????????? is the value at fuel stream inlet

Mixture fraction can also be related to excess air and fuel-air equivalence ratio. 

The other parameter that is incorporated in non-premixed modeling is 

• the interaction of turbulence and 
• chemistry is accounted for with a probability density function (PDF).

The simulation or the modeling of a BERL combustor can be done using CFD software in Ansys, by which we can know the reactions and other parameters in the combustor. 

Simulation:

Step I. The first step, which is a prerequisite requirement for simulation is the creation of geometry and meshing. 

• Geometry creation- the geometry creation includes the making of the BERL combustor and the dimension of the combustor. 
• Meshing creation-includes scaling of the combustor and making all domains in mm. 
• Once scaling is done, the checking of the mesh is necessary, as it gives/tells that the quality of the mesh is good and perfect. 

Step II. The second step that is necessary for simulation is the solver, this step is very essential in the choice of the solver. The solver can be either for energy or pressure or for both based on the type of flow and the conditions which it is working

Step III. After the solver is set, the next step is to set the boundary conditions which include the mixture fraction value and the value of the fuel with mole fractions. 

Step IV. The next step allows you to set the parameters like density, temperature, velocity, etc. which are necessary for the process to take place. 

Step V. In the final step, we just need to select the parameter which has to be varied and then check its impact inside the combustor and to set up the best parameters for the working of the combustor. 

With this simulation, we can get the temperature profile, mass fraction of a particular compound/element, and also the impact of combustion inside the combustor. 

We can also see how each parameter varies the entire combustor application and we can know how it works under extreme conditions. The condition inside the combustor may vary with time and also the fuel used inside it. 

SLDYK
Kit required to develop Modeling of Non-premixed Methane BERL Combustor through CFD Approach using ANSYS:

• ANSYS

Technologies you will learn by working on Modeling of Non-premixed Methane BERL Combustor through CFD Approach using ANSYS:

• ANSYS
• Mechanical

Any Questions?