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No rating yet Subject: Re: Modelling Teed Hydraulic cylinder Author: Todd Meidinger Date: 2000-11-30 10:47:00Yes, I do in fact use working model. I can get the "Rigid Body" cylinder forces from this package. I also can get the cylinder forces from ANSYS by first doing a symmetrically loaded analysis using link 8's for cylinders. The numbers from the rigid body analysis and the ANSYS symmetric/link8 analysis are very close. I like the numbers from ANSYS since the small deflections are included. I have found in both applications and hand calculations that the cylinder loads remain the same when the same loading is shifted to one side. What I cannot simulate well is keeping the force vector in line with the cylinder axis as the structure deforms under the side loaded case. Using the forces to replace the cylinders is a fair approximation, but it brings up some minor issues.
Keep in mind, I AM able to perform these analysis with reasonable accuracy. I am looking for a more elegant (and a little more accurate, real life) way of doing this.
I thought perhaps there was already a element, or keyopt that maybe I was missing that ANSYS already had this capability. It is such a trivial and common application....at first glance! :)
Oh well,
How would one go about requesting a Force driven, length independent element type. I thought that the LINK11 was supposed to do this and I was just using it improperly. After playing with Link 11, I really don't understand its usefulness as a force member. Applying a force to face 2 does not allow its length to change. In my analysis, it acts like a link8. Applying the displacement to face 1 woks great to be able to move things, but you have to "know" the displacement. This element is very close to what I need, just doesn't seem to work properly as a force driven actuator. Am I missing something here?? I hope so.
>I was looking for a better mouse trap. Ever thought about doing this in a kinematics program like Working Model? I think the ASME sofware archive has some kinematics programs that would make short work of it.
Christopher Wright P.E. |"They couldn't hit an elephant from chrisw@s... | this distance" (last words of Gen. ___________________________| John Sedgwick, Spotsylvania 1864) http://www.skypoint.com/~chrisw