Verification of code : Solution and therectical values dont match

vishnukmd7 · December 22, 2010, 07:54

The problem is a I beam (HE 120A Beam) clamped at both ends ( no freedom of displacement or rotation).Length is 3m.The code I wrote is the following :
/PREP7
MP,EX,1,2e11
MP,NUXY,1,0.3
ET,1,188,,,,2
SECTYPE,2,BEAM,I,IBEAM
SECDATA,120e-3,120e-3,114e-3,8e-3,8e-3,5e-3
SECNUM,2
K,,0,0
K,,3,0
L,1,2
KESIZE,ALL,0.1
LMESH,ALL
FINISH
/SOLU
NSEL,S,LOC,X,1
F,12,FY,-30e3
NSEL,S,LOC,X,0
D,1,all,0
NSEL,S,LOC,X,3
D,2,all,0
nsel,all
ANTYPE,STATIC,NEW
SOLVE

I'm getting HUGE differences between the analysis value and theoretical value.( I used the Euler Bernoulli method to solve but even then the answers should be close by at least ). Why is this happening? Is something wrong with the code? Please help.

vishnukmd7 · December 22, 2010, 08:04

And even more problematic for me is the modeling of simply supported beams.
When I change the D code line in the code to d,1,uy,0 and d,2,uy,0 and try to execute the same code , nothing happens.No errors in the code , but no nodal solutions available. what am i doing wrong?

vishnukmd7 · December 22, 2010, 10:35

Well , I figured out the problem with the first problem.The moment of inertia is getting registered wrongly with the ansys program for some reason. Instead of 5.99e-8 its reading 2.somethinge-8.
Any idea why this is happening?

vishnukmd7 · December 27, 2010, 05:27

I'm rather disappointed with the lack of response.Anyway , i figured out the problems.Here is the completed report in case any one is interested : http://tinyurl.com/39uoghc at https://sites.google.com/site/vishnukmd7/

December 22, 2010, 07:54	Verification of code : Solution and therectical values dont match	#1
vishnukmd7 New Member Vishnu Prasad Join Date: Sep 2010 Location: Goa Posts: 19 Rep Power: 16	The problem is a I beam (HE 120A Beam) clamped at both ends ( no freedom of displacement or rotation).Length is 3m.The code I wrote is the following : /PREP7 MP,EX,1,2e11 MP,NUXY,1,0.3 ET,1,188,,,,2 SECTYPE,2,BEAM,I,IBEAM SECDATA,120e-3,120e-3,114e-3,8e-3,8e-3,5e-3 SECNUM,2 K,,0,0 K,,3,0 L,1,2 KESIZE,ALL,0.1 LMESH,ALL FINISH /SOLU NSEL,S,LOC,X,1 F,12,FY,-30e3 NSEL,S,LOC,X,0 D,1,all,0 NSEL,S,LOC,X,3 D,2,all,0 nsel,all ANTYPE,STATIC,NEW SOLVE I'm getting HUGE differences between the analysis value and theoretical value.( I used the Euler Bernoulli method to solve but even then the answers should be close by at least ). Why is this happening? Is something wrong with the code? Please help.

December 27, 2010, 05:27	Solved	#4
vishnukmd7 New Member Vishnu Prasad Join Date: Sep 2010 Location: Goa Posts: 19 Rep Power: 16	I'm rather disappointed with the lack of response.Anyway , i figured out the problems.Here is the completed report in case any one is interested : http://tinyurl.com/39uoghc at https://sites.google.com/site/vishnukmd7/ Last edited by vishnukmd7; January 3, 2011 at 06:48.

December 22, 2010, 08:04		#2
vishnukmd7 New Member Vishnu Prasad Join Date: Sep 2010 Location: Goa Posts: 19 Rep Power: 16	And even more problematic for me is the modeling of simply supported beams. When I change the D code line in the code to d,1,uy,0 and d,2,uy,0 and try to execute the same code , nothing happens.No errors in the code , but no nodal solutions available. what am i doing wrong?

December 22, 2010, 10:35		#3
vishnukmd7 New Member Vishnu Prasad Join Date: Sep 2010 Location: Goa Posts: 19 Rep Power: 16	Well , I figured out the problem with the first problem.The moment of inertia is getting registered wrongly with the ansys program for some reason. Instead of 5.99e-8 its reading 2.somethinge-8. Any idea why this is happening?