the backflow volume fraction of multiphase model

wuming · May 16, 2019, 10:44

hey all
in Euler multiphase modeling, i set the backflow volume fraction of the second phas as 1，but it still flow out of the boundary.Is the backflow volume fraction just an initial value of the calculation?

BlnPhoenix · June 4, 2019, 05:53

Part of the secondary phase will flow outward as it's supposed to be and part comes back into the domain (=backflow) usally not wanted. So i'm not sure what exactly you mean.

wuming · June 6, 2019, 03:52

Quote:

Originally Posted by BlnPhoenix

Part of the secondary phase will flow outward as it's supposed to be and part comes back into the domain (=backflow) usally not wanted. So i'm not sure what exactly you mean.

I used to think that the backflow fraction was set to 1, then the second phase was all reflowed,so that only the primary phase flow out from outlet, and the second phase remained in the domain. But the actual simulation results show that second phase still flowing out.

May 16, 2019, 10:44	the backflow volume fraction of multiphase model	#1
wuming New Member wuming Join Date: Nov 2018 Posts: 26 Rep Power: 8	hey all in Euler multiphase modeling, i set the backflow volume fraction of the second phas as 1，but it still flow out of the boundary.Is the backflow volume fraction just an initial value of the calculation?

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June 4, 2019, 05:53		#2
BlnPhoenix Senior Member Join Date: Aug 2014 Location: Germany Posts: 292 Rep Power: 14	Part of the secondary phase will flow outward as it's supposed to be and part comes back into the domain (=backflow) usally not wanted. So i'm not sure what exactly you mean.