Learning Forum

[BVH]

Hello everybody,

I'm trying to simulate a non-premixed combustion of C2H4 with N2O, but the results of my pdf table seem odd. The combustion takes place in a combustion chamber at around 23 bars with a convergent-divergent nozzle as exhaust.

Problem 1: When I calculate the pdf table (with parameters hereunder), I get "Warning! Rich Flammability Limit (0.192) is greater than double stochiometric (2 * 0.039)", which is not the correct stochiometric mixture fraction and moreover this value changes when I change the equilibrium operating pressure.

Problem 2: When I display the pdf table (2D curve, mean temperature) for a constant value of the scaled heat loss/gain, the results close to mixture fraction = 0 are incorrect. I joined an image to show this problem (index 6 for scaled variance). The problem can be better visualised on 3D curves, but it is hard to create a good image of this.

PDF_table_error.jpg

[RK]

Hello, nAs Ansys employees, we will not be able to view the attached image. Can you please insert the image instead? Thank you. n

[BVH]

sorry, my badn