dpm and edc convergence

luigi

i'm studing a combustion chamber feeded by injection of liquid kerosene. i use the dpm model with a plain orifice atomizer. when i simulate combustion with finite-rate\ed model everything is ok; the fuel evaporate fastly and burn with good efficency. if i use the edc model the droplet takes a longer time to evaporate and this cause the extintion of the flame in a region but the bigger problem is that the continuity and energy residual doesn't go under 10-2. i've tried to change under-relaxation factor but there's no changes. my setting for dpm are: steady particle tracking; 1 iteration per 10 continous flow it. edc- defalt settings an 1 iteration per flow it ( i tried to increase this value butnothing change)