Problem Description B
We will be creating a solid model of the Spindle Base shown in the following figure.![](http://www.mece.ualberta.ca/tutorials/ansys/BT/Solid/images/BModel.gif)
Geometry Generation
We will create this model by creating the base and the back and then the rib.
Create the Base
- Create the base rectangle
WP X (XCORNER) WP Y (YCORNER) WIDTH HEIGHT 0 0 109 102 - Create the curved edge (using keypoints and lines to create an area)
- Create the following keypoints
You should obtain the following:X Y Z Keypoint 5 -20 82 0 Keypoint 6 -20 20 0 Keypoint 7 0 82 0 Keypoint 8 0 20 0 - Create arcs joining the keypoints
Main Menu > Preprocessor > (-Modeling-) Create > (-Lines-) Arcs > By End KPs & Rad - Select keypoints 4 and 5 (either click on them or type 4,5 into the command line) when prompted.
- Select Keypoint 7 as the center-of-curvature when prompted.
- Enter the radius of the arc (20) in the 'Arc by End KPs & Radius' window
- Repeat to create an arc from keypoints 1 and 6
- Create a line from Keypoint 5 to 6
Main Menu > Preprocessor > (-Modeling-) Create > (-Lines-) Lines > Straight Line
L,5,6 - Create an Arbitrary area within the bounds of the lines
Main Menu > Preprocessor > (-Modeling-) Create > (-Areas-) Arbitrary > By Lines
AL,4,5,6,7 - Combine the 2 areas into 1 (to form Area 3)
Main Menu > Preprocessor > (-Modeling-) Operate > (-Booleans-) Add > Volumes
AADD,1,2
- Create the following keypoints
- Create the 4 holes in the baseWe will make use of the 'copy' feature in ANSYS to create all 4 holes
- Create the bottom left circle (XCENTER=0, YCENTER=20, RADIUS=10)
- Copy the area to create the bottom right circle (DX=69)
(AGEN,# Copies (include original),Area#,Area2# (if 2 areas to be copied),DX,DY,DZ) - Copy both circles to create the upper circles (DY=62)
- Subtract the three circles from the main base
(ASBA,3,ALL)
- Extrude the base
Preprocessor > (-Modeling-) Operate > Extrude > (-Areas-) Along Normal - The following window will appear once you select the area
- Fill in the window as shown (length of extrusion = 26mm). Note, to extrude the area in the negative z direction you would simply enter -26.
Create the Back
- Change the working planeAs in the previous example, we need to change the working plane. You may have observed that geometry can only be created in the X-Y plane. Therefore, in order to create the back of the Spindle Base, we need to create a new working plane where the X-Y plane is parallel to the back. Again, we will define the working plane by aligning it to 3 Keypoints.
- Create the following keypoints
X Y Z #100 109 102 0 #101 109 2 0 #102 159 102 sqrt(3)/0.02 - Align the working plane to the 3 keypointsRecall when defining the working plane; the first keypoint defines the origin, the second keypoint defines the x-axis orientation, while the third defines the orientation of the working plane.
(Alternatively, type KWPLAN,1,100,101,102 into the command line)
- Create the following keypoints
- Create the back area
- Create the base rectangle (XCORNER=0, YCORNER=0, WIDTH=102, HEIGHT=180)
- Create a circle to obtain the curved top (XCENTER=51, YCENTER=180, RADIUS=51)
- Add the 2 areas together
- Extrude the area (length of extrusion = 26mm)
Preprocessor > (-Modeling-) Operate > Extrude > (-Areas-) Along Normal
VOFFST,27,26 - Add the base and the back together
- Add the two volumes together
Preprocessor > (-Modeling-) Operate > (-Booleans-) Add > Volumes You should now have the following geometry
VADD,1,2Note that the planar areas between the two volumes were not added together. - Add the planar areas together (don't forget the other side!)
Preprocessor > (-Modeling-) Operate > (-Booleans-) Add > Areas
AADD, Area 1, Area 2, Area 3
- Add the two volumes together
- Create the Upper Cylinder
- Create the outer cylinder (XCENTER=51, YCENTER=180, RADIUS=32, DEPTH=60)
Preprocessor > (-Modeling-) Create > (-Volumes-) Cylinder > Solid Cylinder
CYL4,51,180,32, , , ,60 - Add the volumes together
- Create the inner cylinder (XCENTER=51, YCENTER=180, RADIUS=18.5, DEPTH=60)
- Subtract the volumes to obtain a hole
- Create the outer cylinder (XCENTER=51, YCENTER=180, RADIUS=32, DEPTH=60)
Create the Rib
- Change the working plane
- First change the active coordinate system back to the global coordinate system (this will make it easier to align to the new coordinate system)
Utility Menu > WorkPlane > Align WP with > Global Cartesian (Alternatively, type WPCSYS,-1,0 into the command line) - Create the following keypoints
X Y Z #200 -20 61 26 #201 0 61 26 #202 -20 61 30 - Align the working plane to the 3 keypointsRecall when defining the working plane; the first keypoint defines the origin, the second keypoint defines the x-axis orientation, while the third defines the orientation of the working plane.
(Alternatively, type KWPLAN,1,200,201,202 into the command line)
- First change the active coordinate system back to the global coordinate system (this will make it easier to align to the new coordinate system)
- Change active coordinate systemWe now need to update the coordiante system to follow the working plane changes (ie make the new Work Plane origin the active coordinate)
Utility Menu > WorkPlane > Change Active CS to > Working Plane
CSYS,4 - Create the area
- Create the keypoints corresponding to the vertices of the rib
X Y Z #203 129-(0.57735*26) 0 0 #204 129-(0.57735*26) + 38 sqrt(3)/2*76 0 - Create the rib area through keypoints 200, 203, 204
Preprocessor > (-Modeling-) Create > (-Areas-) Arbitrary > Through KPs
A,200,203,204
- Create the keypoints corresponding to the vertices of the rib
- Extrude the area (length of extrusion = 20mm)
- Add the volumes together
You should obtain the following:
![](http://www.mece.ualberta.ca/tutorials/ansys/BT/Solid/images/BFinal.gif)
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