2/20/2008
Mesh for 180 pipe using the baffle spacing of pilot plant: 0.1 x 1 m Mesh vertical (first length = 0.001, interval count = 100) Horizontal (successive ratio = 1.1, inverval count = 20)
Now solve in fluent (Using parameter from pilot plant)
vol flow rate = 109 L/min = 1.82e-3 m^3/s
pipe diameter = 3in = 0.0762m
area = 0.018m^2
velocity = Q/A = 0.1m/s
2/18/2008
Mesh for 180 pipe bend done for both sharp turn and smooth turn. Mesh criteria: successive ration 1.1. Interval size = 0.1 for vertical line and 0.05 for horizontal line.
2/15/2008
Tutorial of flow over mixing elbow.
Used own mesh. Use the tutorial method. Obtained the solution (with back flow warning). Result not quite the same. Maybe due to different mesh. They used unstructured mesh, I used structured mesh.
Good thing to note:
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When setting boundary conditions of the inlet and outlet, they use
Turbulence Specification Method: Intensity and Hydraulic Diameter. (Turbulence intensity, hydraulic diameter)
Use pressure outlet for the outlet boundary condition.
Use adapt --> Gradient > deselect coarsen >compute > enter value for refine threshold > mark >manage.
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Create a mesh with more elements. Following the same steps, still not quite the same as the tutorial solution.
Ok, after this, I will try using hydraulic diameter to our pipe bend problem and see whether the result changes.
Remember to use 3ddp when open fluent for the previous file.
2/7/2008
3D 90 degree elbow
First mesh face using Quad, Submap, then mesh volume.
Interval size: 0.001
Take too much time.
Fail, only mesh the faces
2nd mesh face using Quad, Submap (interval size 0.005), only Stair steps option are available for mesh volume (interval size 0.001).
Workable. Maybe not... still too long...
Use Quad Submap 0.005, use stair steps 0.005. Get result.
In Fluent:
Use K-e model. Use liquid water. Set inlet = -39.9 in x direction
Got the mesh. Now need to compare.
Mesh 5 is the good one! The velocity vector compares ok with the data. The difference might be due to our mesh not refine enough causes truncation error.