Learning Forum

[Hitendra Singh]

So i want to study the temperature, velocity and pressure of the flow coming out of cd nozzle after the combustion process inside the chamber. 2 different inlets are provided, one for liquid methane (LNG) and another for liquid oxygen (LOx) and i want them to get mixed and ignite inside the chamber. I am not understanding why the flow is going downwards and velocity of flow is maximum at throat and decreasing further. Any suggestion would be appreciated.

 

Mesh:

Target skewness: 0.9 (Default)

Number of nodes: 176174

Number of elements: 175014

 

Setup:

1. Solver:

Pressure based, steady and absolute

 

2. Model:

k-epsilon standard with standard wall function and curvature correction

 

3. Species:

Non premixed combustion with Inlet diffusion, chemical equilibrium and non-adiabatic enabled at standard atmospheric operating pressure.

3.1.  Boundary:

CH4 = 1 and O2 = 1 with fuel temperature 90K and oxidizer temperature 60K.

3.2. Calculated Pdf table.

3.3. Radiation is enabled as Discrete ordinates 

 

4. Boundary Condition:

Fuel inlet (mass flow inlet)

Mass flow inlet = 0.017 kg/s

Initial Gauge pressure = 2465000 Pa

Turbulent intensity = 10%

Mean Mixture Fraction = 1

Mixture Fraction Variance = 0

 

 

Oxygen inlet (mass flow inlet)

Mass flow inlet = 0.026 kg/s

Initial Gauge pressure = 2465000 Pa

Turbulent intensity = 10%

Mean Mixture Fraction = 0

Mixture Fraction Variance = 0

 Outlet (pressure outlet)

Gauge pressure = 96500 Pa

Initialization method: Hybrid

 

[Vijay Narayan]

Hi Hitendra,

Is the combustion complete? has all the reactants converted to products ?

Could you share the contours of mass fraction of O2, CH4 and product species like CO2 and H20.