| enthusiast |
February 27, 2022 00:42 |
What is km and epsilonm in MultiphaseEulerFoam?
2 Attachment(s)
I am trying to validate MultiphaseEulerFoam (twoPhaseEulerFoam) for a 2 phase (water and air) flow through a horizontal pipe.
I am using Open Foam version 8 and I am using the below-mentioned research paper for validation.
Ekambara, K.; Sanders, R. S.; Nandakumar, K.; Masliyah, J. H. (2008): CFD simulation of bubbly two-phase flow in horizontal pipes. In Chemical Engineering Journal 144 (2), pp.*277–288. DOI: 10.1016/j.cej.2008.06.008.
As per the reacheacr work I have considered 50.4mm dia pipe with 9m length,
superficial gas velocity of 0.42 m/s and superficial liquid velocity is 4.67 m/s and average gas volume fraction is 0.085.
I am using the bubble column tutorial case as a reference.
Regarding the mesh quality, I have no issues since I have very good values of nonorthogonality and skewness.
In 0 folder there is a separate km and epsilonm. Could someone please explain what are these?
The simulation crashes since my case is developing large amounts of bounding km and bounding epsilonm. Also, the epsilon does not converge.
I have attached all the details regarding the case file.
Your help is reallz appreciated.
Thank you.
HTML Code:
Mesh stats
points: 314154
internal points: 273132
faces: 898010
internal faces: 856990
cells: 292500
faces per cell: 6
boundary patches: 3
point zones: 0
face zones: 1
cell zones: 1
Overall number of cells of each type:
hexahedra: 292500
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0
Checking topology...
Boundary definition OK.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
Number of regions: 1 (OK).
Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
inlet 260 279 ok (non-closed singly connected)
walls 40500 40536 ok (non-closed singly connected)
outlet 260 279 ok (non-closed singly connected)
Checking geometry...
Overall domain bounding box (0 -0.0252 -0.0252) (9 0.0252 0.0252)
Mesh has 3 geometric (non-empty/wedge) directions (1 1 1)
Mesh has 3 solution (non-empty) directions (1 1 1)
Boundary openness (-2.3893e-17 -5.72203e-15 1.9e-15) OK.
Max cell openness = 3.03186e-16 OK.
Max aspect ratio = 8 OK.
Minimum face area = 1.25e-06. Maximum face area = 3.95216e-05. Face area magnitudes OK.
Min volume = 1e-08. Max volume = 1.46563e-07. Total volume = 0.0178609. Cell volumes OK.
Mesh non-orthogonality Max: 30.8909 average: 6.3203
Non-orthogonality check OK.
Face pyramids OK.
Max skewness = 0.729903 OK.
Coupled point location match (average 0) OK.
Mesh OK.
End
Attachment 88526
Attachment 88527 |
