NUMECA Training_case_3_centrifugal_pump_61
FINE TM/Turbo 6.1-1 -Turbomachines
Training Session
Centrifugal Pump -Practice
Relative Velocity Field Centrifugal Pump Mesh
Content
Centrifugal Pump
Autogrid TM Software (03)
Practice
FINE TM Software (24)
Practice
CFView TM Software (48)
Practice
Practice
Centrifugal Pump
Autogrid
TM Total Mesh
Meridional
View
Mesh Generation
OK?
Step 3 : Define Blade Topology
?H, I or HOH mesh ?Blunt ?Splitter ?Bulb ?Propeller
Step 6 :Volumic Mesh
?Generation of the volumic mesh ?Checking the negative cells
?Checking the grid quality (orthogonality, aspect ratio, grid continuity)?Boundary Conditions Type
Step 7 : Save Template & Grid
Step 1 : Open IGG/Autogrid ?Hub &Schroud Definition
?Suction & Pressure Sides definition
Step 2 : Define Blade Geometry
Step 4:Meridional Control ---?Nbre of points ?Tip & Hub Clearance
> Flow Paths
Step 5 : Mesh Blade -to -Generation of 2D mesh
blade on Hub & Shroud
No
Yes
Step1: Open Autogrid TM
1.Open IGG Session
1
2.Open Autogrid Window
2
Step 2 : Define Blade Geometry
7 blades -259,161 nodes
Geometry given in meters
Hub and shroud surface expansion = 0.03 Topology
H/I-mesh
Spanwise grid points : 41
Azimuthal grid points : 45
Streamwise grid points : 33 -65 -33
Cell width along walls = 1 10-5
1.If necessary: in order to see the
Quick Access Pad, select in
File/Preferences/Layout the
Quick Access Pad& Apply 2.Select Set-Up in the Icon Bar 1a
1b
1c
1d
2
3a
3b
3c
Set-Up Window
3.Activate Select Geometry File in the
1.Activate Surface Edition -Modify Expansion to0.03
1
2.Activate Geometry Characteristics -Modify Nbre of Blades to7
2
1.
Activate Topology in the Set-Up Window
Nbre of points
Clustering
2.Select H&I Topology
3.
Modify Nbre of pts & clustering -
Next ---> “Flow Paths”Created
blade
shroud
hub
streamsurface spanwise
streamwise
azimuthal
2
Step 3 : Define Blade Topology
1
4
Spalart -Allmaras
3
45
1.Deactivate Expert Mode
2.No Tip Clearance
3.Apply
4.
Next
Step 4 : Meridional Control
1
3
4
2
Flow Paths
2D Mesh
Step5 : Mesh Blade-to-Blade on Hub & Shroud 1.Activate Points Distribution
Modify Nbre of points
2.Apply
3.Activate Mesh
Put the Smoothing Step to 20
Activate the Multiblock Smoother
Orthogonality blade-to-blade to 0.0125%
Initial Cell width blade-to-blade to 1e-5
Cst Cells blade-to-blade to 10
4.Apply
If necessary
A.Right-Click on the edges to change local Cell
Length or Clustering Expansion Ratio
B.Activate Expert (if necessary)
Adapt Streamwise Clustering
Adapt Streamwise Matching Points (I mesh)3
1
B
Left-click –value -
2-4
A 3 1
1 Left-click on Projection Point Move Interactively
Blade -to -Blade Shape Control (Optional)
3
1
2
A
1.
Extension Control
Impose in degree angular (theta) position of Inlet & Outlet in
Relative or Absolute on both Hub & Shroud views 2.Activate Solid Angles
Impose in degree trailing & leading edge angle in Relative on both Hub & Shroud views 3.Update Blade-to-Blade Mesh Apply & Accept the modifications
If necessary
A.
Activate Expert
Blunt Control
Extension Surface Parameters
Tangent Weight at Leading/Trailing edge
1.
3D Mesh Generation 2.
Yes
3.
Check Grid Quality & Negative Cells
4.
Close the window
Step 6 :Volumic Mesh
1
2
3
4
Quality C ontrol –Tool
1.Select 3D View
2.
Deactivate Mesh
3.
To access the Grid Quality analysis tool, select the "Grid/Grid Quality " menu.
To analyse the ORTHOGONALITY
?Select all blocks -<0>
?Select the "orthogonality" type in the "mesh Quality" dialogue box ?Click on the "Show chart"/"Hide chart" to toggle a chart display ?
Display the range of cells by clicking directly on the Chart Bar
Orthogonality > 10°
Solution
?Check Clustering ?Check Smoothing OR
?Use I-mesh 1
2a
2b
3a
3b
3c
3d 3e
3f 3g
3h
To analyse the EXPANSION RATIO
?select the ”Expansion Ratio" type in the "mesh Quality" dialogue box ?Click on the "Show chart"/"Hide chart" to toggle a chart display
?Display the range of cells by clicking directly on the Chart Bar
?
Select More Info to see maximum value in the concerned block.
Expansion ratio ≤3
To analyse the ASPECT RATIO
(i_direction/j_direction)
?Select all blocks -<0>
?Select the " Aspect Ratio " type in the "mesh Quality" dialogue box
?Click on the "Show chart"/"Hide chart" to toggle a chart display
?Display the range of cells by clicking directly on the Chart Bar
?
Select More Info to see maximum value in the concerned block.
Aspect ratio < 5000
Mesh Quality Improvements –Mesh Quality at Boundaries 1
2
3
Mesh Quality Defined at Boundaries
?ORTHOGONALITY
?ANGULAR DEVIATION (CON -PER)
?EXPANSION RATIO (CON -PER)
?CELL WIDTH
1
Mesh Quality –Negarive Cells 3
Mesh Quality Improvements –Negative Cells
2
4