Hello Richard.... t hank you for the reply.

But the link you provide does not provide enough data for solving my problem.

I am modeling a piping system with 6 Flex-Hoses (Gas Tubine piping). The Axial Stiffness of the Flex hose is very much larger than the Lateral stiffness. During installation, we install the Flex Hose with Axial offset ( after installation, the shape of the Flex Hose will be an arc). So even if the Pipes at the end of the Flex Hose move axially, the flexhose experience no Axial growth /compression. So in operation, the stiffness of the Flex Hose in the axial direction will be much less than the actual Axial Stiffness. How can I simulate this effect in CAESAR ?

A approximation we did was, we gave the Axial stiffness value same as the lateral stiffness of the flex hose. We assumed that even though the Pipe move in Axial direction, the flex hose will move out (or in) in the lateral plane. Can this assumption be justified ?

Thanks and regards, Anish.

There are two points to consider here:

1) Piping programs, such as CAESAR II, utilize the 3D Beam Element. As such, you can't ask these programs to evaluate behavior that is beyond the capabilities of this element - small deflections, small angles, dominated by bending. You can't model a flexible hose with a 3D beam element.

2) The stiffness of the flexible hose is so much less than that of the pipe, it (the flexible hose) has no effect on the pipe system. Therefore, you can model the system up to the pipe/hose connection, and stop. The pipe has essentially a free end.

If you are concerned about the behavior of the flexible hose, you will need to consult the hose manufacturer for details and recommended practices. You can not evaluate flexible hose in CAESAR II.