whether DEM or Eulerian approach for high solidup

CFDUSERIN

hi everybody

i am having bit of confusion about the choosing correct approach for multhiphase with high dispersed phase holdup for example in case of gas fluidized bed with high solid up, whether we have choose Eulerian-discrete element method(DEM) or Eulerian-Eulerian two fluid method. in dense bed, particle -particle interaction will be dominant when compared to other force, should we use DEM based approach for dense bed? otherwise any criteria for high solid holdup for choosing DEM or two fluid approach

one more question about high solid up is there any range for solid holdup for dense and medium bed.. or under what basis classified the dense bed

with regards CFDUSERIN