Simple Question/Extreme Headache: Creating area from lines 1

[RVswift]

I am trying to create an area from lines but get the error "Keypoint 1 is referenced by only one line. Improperly connected line set for AL command". I have checked all my lines match up and form an area that is all in the same plane but I still get the error. If I start the command with a different line the error comes on a different keypoint.

If I use the GUI and pick the lines it works so really do not understand why the AL,1,2,3..... command will not work!!

If you want to see the mystery I've put the code below. Any help greatly appreciated!

I've read the help files, seems like a simple command so I don't understand why it wont work. I don't understand the following from the help file on AL command though.

"The positive normal of the area is controlled by the direction of L1 using the right-hand rule. A negative value of L1 reverses the normal direction. If L1 = ALL, use all selected lines with L2 defining the normal (L3 to L10 are ignored and L2 defaults to the lowest numbered selected line). If L1 = P, graphical picking is enabled and all remaining arguments are ignored (valid only in the GUI). A component name may also be substituted for L1."


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/TITLE, Dynamic Analysis of Load Cell
/FILNAME, Dynamic,0
/PREP7

! GEOMETRIC VARIABLES
x1 = 100
x2 = 68
y1 = 120
y2 = 26
r1 = 18
r2 = 6
r3 = 12
z1 = 45

! KEYPOINTS
K,1,0,0,0
K,2,x1,0,0
K,3,x1,y1,0
K,4,0,y1,0

K,5,0,y2,0
K,6,x2,y2,0
K,7,x2+r2,y2+r2,0
K,8,x2,y2+2*r2,0
K,9,0,y2+2*r2,0

K,10,x1,y1-y2-2*r2,0
K,11,x1-x2,y1-y2-2*r2,0
K,12,x1-x2-r2,y1-y2-r2,0
K,13,x1-x2,y1-y2,0
K,14,x1,y1-y2,0

K,15,x2,y2+r2,0
K,16,x1-x2,y1-y2-r2,0

K,17,x1/2,y1/2,0
K,18,x1/2,0,z1/2
K,19,x1/2,y1,z1/2

!LINES
L,1,2
L,2,10
L,10,11
LARC,11,12,16,r2
LARC,12,13,16,r2
L,13,14
L,14,3
L,3,4
L,4,9
L,9,8
LARC,8,7,15,r2
LARC,7,6,15,r2
L,6,5
L,1,5
CIRCLE,17,r1

!AREA
AL,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18 !ERROR USING THIS COMMAND, it does work for AL,15,16,17,18??

 

[Drej]

You cannot create a single area for two seperate entities in a single command. Select lines 1,14 first and then create the area, then select the remaining lines and create the second area thus:

! REPLACE AL,1,2,3,4,5...... with:
lsel,s,line,,1,14
al,all
alls
lsel,s,line,,15,18
al,all
alls


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[RVswift]

Thank you very much!

I had tried to do each entity separate but using the AL,1,2,3,all the way to 13,14, command it didn't work. It did work for the AL,15,16,17,18 however :s

Thank you for showing me the LSEL command as this works for me and is useful to know!

One question I would like to know is what the alls command does in your code? I couldn't find in ANSYS documentation, google and it doesn't come up with all "tooltip" when I type it into ansys command bar.

Regardless thank you for your very quick help!

 

[Drej]

alls is a truncation of allsel. This selects all entities but you shouldn't need it, I do it just for security. Tip: you only need the first four letters of any command for ANSYS to recognise it.


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