Xin Yan
M.Sc. Student Department of Mechanical Engineering University of Saskatchewan Supervisor: Prof. Donald Bergstrom Prof. Daniel Chen
Email: [email protected] Office: 3C89
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Application of CFD in the research of bioreactors
Flow inside the scaffolds. Flow around the scaffolds.
3[1] http://www.bose-electroforce.com/products/specs/BioDynamic_Test_Instrument.pdf
[1]
Two approaches: commercial software in-house codes
Physical model
Mathematical model-
governing equations
Numerical model-
discretized governing equations
Numerical results
Boundary conditions
Initial conditions
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Why commercial software?? Complicated geometry Good visualization Easy to learn
5[2] http://www.aspsys.com/userfiles/image/fluent3.jpghttp://www.aspsys.com/userfiles/image/fluent3.jpgv
[2][3]
[1]http://www.launchpnt.com/fileadmin/cfd-analysis1.jpg
[1]
[3]http://www.lilitoys.com/Article/changshi/hangmo/200709/11.html
Choices??
CFX Fluent Numeca ……….
A module in ANSYS Single environment User friendly Quick and straightforward Fast and accurate CFD
solver Powerful visualization
capability
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Useful sources for learning CFX
1. Help in menu bar 2. CFD online http://www.cfd-online.com
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Geometry: DesignModeler Pre-processor Mesh: CFX-Meshing CFX-Pre Solver CFX-Solver
Post-processor CFX-Post
Simulation Process
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Pipe flow (laminar)
U
L
D
Laminar Flow Inlet: U=0.01m/s D= 20mm L=100mmWater: density 997kg/m3
Dynamic viscosity: 8.9×10-4kg/m·s Red=225Flow rate: 0.00313kg/s
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ANSYS workbench:DesignModeler (.agdb) Sketching Modeling Import External Geometry file
Modeling 1)Create>Primitives>Cylinder2)Set up the details3)Generate4)How to see the geometry model
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ANSYS workbench: CFX-Mesh1)Specify regions2)Set spacing for each region3)Inflation mesh4)Generate the surface mesh
5)Generate the volume mesh
6)Save and create CFD simulation with mesh
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ANSYS workbench: CFX-Pre1)Create a domain2)Set up boundary conditions
3)Set solver control4)Set material properties
inletoutletsolid wall
IF the regions are not specified when meshing.
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ANSYS Workbench: CFX-Solver
1) Save and write
solver file (.def)
2) Special initial file if needed
3) Start run
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ANSYS Workbench: CFX-post1)Create locations (point, line, plane,…)2)Create contour, vector, stream line,…3)Create chart, table.
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Laminar flow in a pipe
Potential problems How to solve it?
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14 R
r
dz
dpRu
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[1]
[1] Pipe flow. Maryam Einian
Before refine
Maximum spacing:5mm
After refine
Maximum spacing: 2mm
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Laminar flow in a pipe
Result withRefined mesh
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22
14 R
r
dz
dpRu
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[1]
[1] Pipe flow. Maryam Einian
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Finish the simulation. Compare the velocity profile of developing and
fully developed flow in a pipe. Plot the mean velocity profile at the exit and
compare it with analytical solution. Submit your simulation results (including the
velocity profile and the vector figure) and comments.
Please send it to [email protected] day : September 29th
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