Re: Dynamic analysis.

From: <Christopher>
Date: Tue Oct 29 2002 - 17:03:00 EST

>I'm looking to do dynamic analysis of normal flow
>lines from oilwells. Please advise in which mode it is
>good to do dynamic analysis and what are the assumed
>values to be used such as frquency value and other
>factors as may be required for hormonic analysis.
You might want to get hold of a book on structural dynamics. A piping system is basically a framework with boundary conditions set by the supports. Frequencies are a part of the structural response and unique to a given system. Part of the analysis is figuring the frequencies. The basic process is to figure the system frequencies and mode shapes. The mode shapes are shape functions--the actual displacement and loading is determined by the excitation. The excitation depends on the loading, possibly seismic or gust loading. Seismic loading is applied using response spectra; harmonic response is the response to steady state sinewave base motion over a range of frequencies.

This isn't much of an answer because your question is too broad. Dynamic analysis gets pretty complicated because it's not very intuitive, but the principles can be found in dynamics textbooks. Piping codes will off some guidance, but it requires a basic understanding of dynamics.

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=dhaHCgxkv-ANHZbWtKbYfolRE7-zN1PkYjdJfL9KdoBdyQ9Gzw4e3wYU5XgqAnbpXc_K6KGrjqjF">chrisw@skypoint.com</a> | this distance" (last words of Gen.

___________________________| John Sedgwick, Spotsylvania 1864)

<a href="http://www.skypoint.com/~chrisw">http://www.skypoint.com/~chrisw</a> Received on Tue Oct 29 17:03:00 2002