fluidized beds

T.Hari

hi friends,

iam simulating fluidized risers,iam having one problem in my results,when i go through the results iam getting the core annular flow in the riser bed,flowing of gas in the centre region and the flow of soid down near the wall.This is what i sholud get,but iam hving one problem here,the vectors near the wall for solid are showing down.so the magnitude should be negative but iam not getting this negative value for mass flux and velocity profiles, but it is showing zero value at the wall for the velocity profile and massflux,these fluxes and velocities should be negative but it is not showing, iam not getting where iam wrong can any one give some valuble sugesstion so that i can get the values of flux and velocity negative.