Script to convert RBE2 to RBE3 or vice-a-versa

sanket_patil

hello everyone,

 

Can anyone tell me how to convert RBE2 elements to RBE3 elements or reverse too (i.e RBE3 to RBE2).

 

Thanks,

Sanket

tinh

Make a foreach loop with each Rbe2, get its indep node and dep nodes, then create rbe3 based on those

sanket_patil

@tinh I am not getting exact idea about how to deal with independent and dependent nodes? can u explain it little?

 

Regards,

Sanket

Q.Nguyen-Dai

Some lines to give you some ideas:

 foreach eid $elemList { 	set config [ hm_getentityvalue elements $eid 'config' 0 ] 	#----- RBE2 ----------- 	if { $config == 55 } { 		set independentNode [hm_getentityvalue elements $eid independentnode.id 0] 		set elemNodes [hm_nodelist $eid] 		eval *createmark nodes 1 $elemNodes 		eval *createmark nodes 2 $independentNode 		*markdifference nodes 1 nodes 2 		set elemNodes [hm_getmark nodes 1] 		puts 'RBE2: $eid = $independentNode \[ $elemNodes \]' 		set new_eID [proc_to_make_RBE3 $independentNode $elemNodes] 	} }

 

tinh

Oh. I remember that it can be changed config.

Enter panel 1d>config edit, select RBE2 and select 'new config' as RBE3 > switch.

 

covadonga

Is the opposite possible? From the panel 1d could a RBE3 be changed to RBE2?

Adriano A. Koga

is there any particular need for this to be performed as a script?

 

In HM you have the 'config edit' panel that has this functionality.

Maybe you will need some extra steps to make sure DOFs and weighting are correct. But sometimes the core funcionality already fits your needs.

 

<?xml version="1.0" encoding="UTF-8"?> 

covadonga

Thank you Adriano, 

No problem on doing the change manually, the conversion RBE2- RBE3 did went well. I am using 1D element to transmit a torque, it seems that RBE3  makes my model more stable, is there a preference between RBE2 and to introduce a moment?

Kind regards

Q.Nguyen-Dai

When you use RBE2, you add an infinite stiffness (rigid) into your structure.

While you use RBE3, you add nothing.

The choice between RBE2/RBE3 depend to your analysis goal.

Adriano A. Koga

for trasmitting moment loads you need to define correctly de DOFs for each node (in both RBE2 and RBE3) so that the central node carries the moment as well.