(72k) Effect of the Grid Generation in Numerical Simulation of Spray Granulation Tower

The nozzle is the core equipment in the Spray Granulation Tower. The separation efficiency of the Tower can be promote by adjusting the swirl intensity. However, the declining nozzle in the Spray Granulation Tower increases the difficulty of geometric modeling; the previous researchers often simplified the structure of the declining nozzle by setting a jetting angle on the straight nozzle when applying the boundary conditions. To ensure the consistency of the rate of flow in the simplified and no-simplified nozzle, the previous researchers often increased the jetting velocity or jetting area, which often leaded to a result deviation between the simulating result and actual result. To compare the difference of the simulating result between the simplified nozzle and no-simplified nozzle, this article researched the flowing distribution of the single nozzle in the Spray Granulation Tower through the three-dimensioned numerical simulating method and experimental method respectively. The comparing result indicates that there are some difference in flowing feature and velocity distribution between the different grid generation method and experimental result. The no-simplified structure of nozzle can weaken the numerical dissipation resulted from the inconsistency between flowing direction and gridding direction near the outlet of the nozzle, that has a longer central jetting area and smaller angle of atomization. The simulating result of no-simplified Spray Granulation Tower coincides with experimental result better, and the tangential velocity of no-simplified nozzle shows better axisymmetric character. Therefore, the simulating result of a Spray Granulation Tower with no-simplified nozzle is more accurate.