Hi

I want to solve the problem about coal combustion burner. I am running DPM simulation using KE model, segregated solver, two way coupled calculation and Stochastic model.

I have set the Max no. of steps to 10000 and a length scale of 10. and the continious phase calculations per DPM is 10. when I run fluent, half of particles are incomplete and seems to be in recirculation flow. I changed the max no. of steps to 15000 and/or a length scale of 20, but it didn't make change so much.

What should I do to make escape them? or Can I ignore these incomplete particles?

Thanks in advance.

What are you trying to get out of your model and what do you think the physical reality is? If these coal particles have burned out and it is just the ash left behind, and you don't care about tracking the ash, then you can probably ignore them.

What is the residence time of the particles? If it is +10 seconds, something in your model may be wrong because that is an unlikely condition. Do you have gravity turned on? Is the particle density realistic? Particle size? Would these particles, in reality fragment? coalesce?

Good luck.

Thanks for your reply, Allan.

I have gravity turned off. Particle density is 1500kg/m3, and size is 20 micron. The residence time of particles are 0-25 seconds, but particles burned out (combusting law was finished) till 2 seconds.

Your comment about ash relieved me, so I can start to check other points.

Thank you!