Hi developers,
I want to simulate a cylindrical spout-fluidized bed with multiple spout gas inlet. There are 5 small tube working as the spout gas inlet tube. There should be fluidizing velocity region at the bottom of the cyclindrical STL. I am wondering how to achieve this in MFIX.
Kind regards
Yuanhe
Is your mesh sufficiently fine to resolve the small inlet tubes? If so you can define a rectangular plane that encompasses all tubes. This will set the same inlet BC for all tubes. If you need 5 different inlet conditions, then you can define 5 rectangular planes around each tube. If the mesh is too coarse to resolve the tubes, you can use point sources instead. You will not model the tubes, only the large cylinder and put the point sources near the bottom of the cylinder.
Hi jeff,
If I want to simulate a multiple jet spouted-fluididzed bed, I need to set a high velocity to the bottom of the tube. Based on your suggestions, I can simply cut the bottom region to small regions and set different velocities. If to do it, I must wipe out the tube extended from the cylindrical reactor bottom, is that right? Thank you.
This all depends on your mesh size compared with the size of the inlet tubes. My guess based on the figure above is the mesh size is about the same as the inlet tubes, which means you cannot resolve them, and they won’t be part of the geometry.
Now you can define square BC regions for each inlet. If you specify the velocity, you may need to adjust its value is the cross section area of the BC inlet is not the same as the inlet tube. Alternatively, you can specify the mass flow rate instead. You can also use point sources and provide mass flow rate (velocity components are not enforced for point sources).