Eddy-Break-Up in Reacfn.f and Sorent.f
 

I have been trying to expand the Eddy-Break-Up mode in prostar with a chemical model. Does anyone know how to call the routine for Eddy-Break-Up from within REACFN or SORENT? After trying to encode EBU myself the results obtained were different from the ones obtained using prostar.

Thanks, Daniel

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

Hi,

I do not know how to call the Star routine. But, there are many types of Eddy Break-Up combustion models that can be implemented. Are you sure you implemented exactly the same model as the Star-Cd model ? For example, it makes sometimes a big difference if you take into account the product term in the minimum sentence or not.

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

Thanks Ossi, Yes, I realize slight variations in the Eddy Break-Up are crucial, but I tried to follow the description in the methodology volume (with the product term). No variation I tried produced the desired results.

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

What exactly are the differences between the built-in Eddy Break-Up model and your own coding ?

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

I built a small model of 2x20 cells in which CH4 and air entered separately at one end and left at the other, I monitored the two models at the first cell by the air inlet and obtained small differences in temperature (about 1%) and larger differences in pressure (about 10%) there was almost no difference in species concentrations or turbulence parameters. In the full model I am solving the discrepancies are much more pronounced (due to the cumulative error I suppose). This could be a problem with the enthalpy source term in SORENT, but how can I test this?

Thanks, Daniel

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

I am afraid I cannot help you much. Except to say that I have experinced difficulties with the usersubroutines in DEC machines. The runs crashed without any reasonable explanations with the reacfn.f subroutine. But this was with the v3100A, I think.

If you are sure that your programming does not differ from the built-in model, then you should contact the CD support in my opinion.

Re: Eddy-Break-Up in Reacfn.f and Sorent.f
 

Thanks Ossi, I have contacted the support, am awaiting thier reply

Daniel