HYPERMESH

Xin Yan

M.Sc. Student Department of Mechanical Engineering University of Saskatchewan Supervisor: Prof. Donald Bergstrom Prof. Daniel Chen

Email: xiy562@mail.usask.ca 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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22

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 xiy562@mail.usask.caDue day : September 29th

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