Hey guys, I am currently working on a project and need to model the tubing configuration as shown in the first attachment. Experimental testing has been completed and I have detailed data for the strain and vibration velocity as required. I need to model this in ANSYS to compare the results. To model the vibration shaker I need to model the rod as a spring with fixed support on the shaker side and a translation constrained in the axial direction on the tube side. I have used SHELL181 for the tubing and tried to use LINK180 for the rod as shown in the second attachment. However, when the mode shapes are calculated, the link doesn't behave as I would expect; the link isn't staying stiff causing a large deflection at the attached node and knocking out the frequency calculations. I'm not very experienced with this software but I think it should be relatively easy to fix. I just think the rod isn't being modelled properly. The only real constants I can use for the link are the area and I have chosen the rigid (classic) option. How can I adjust this? Any thoughts would be greatly appreciated, Cheers!