Learning Forum

[sam67]

I am using Eulerian-Eulerian multi-phase scheme in ANSYS Fluent to model biomass pyrolysis in a fluidized bed reactor. I have introduced the heterogeneous reactions and biomass is converted into lumped products i.e. char, tar and gases. While I am calculating the product yield, it is going beyond 100% which is not correct. What could be the reason for this? Is that because of mass imbalance or reaction kinetics?

 

[DrAmine]

Hi,

Might be a mass imbalance occurring. Please paste the relevant lines from the Fluent console which shows how you calculated the mass.  Moreover paste the input summary of the case here

 

[sam67]

Hi Abenhadj,

Thanks for your response.

I have defined customised functions to determine the amount of products and then calculated the overall yield based upon what is leaving the reactor and what is inside reactor using surface and volume integrals of the customised functions.

For the input summary, I am using three phase system, primary phase is the gas phase, while sand is patched in the column as secondary phase and biomass is entering with a continuous mass flow rate. 

[DrAmine]

Hi,

You do not to do that via custom field function as everything is already available as flux reports under report definition. Perhaps a small adjustment of time scales will alleviate the mass imbalance if still happening.  You need to debug the mass yield every time step.