# need help for aqwa - different between whole cable force and cable section tension?

Discussion in 'Software' started by kojes, May 21, 2012.

1. Joined: May 2012
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### kojesJunior Member

can any body help me???
i have a problem about aqwa...

what is the different between whole cable force and cable section tension?

thank you.

2. Joined: Apr 2011
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### CWTeebsAnomalyGenerator

A cable is subdivided into a number of sections, usually 20 to 40, so the section tension is the tension on a single discretized element of the cable, whereas the whole cable tension is the integral of the cable tensions up to a connection point (e.g. the reaction the fairlead feels).
Hope that clarifies.

CWTeebs

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3. Joined: May 2012
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### kojesJunior Member

thank you for the answer. it is very helpfull. i have final project from my university for the requirement of my graduation. i have compared between "whole cable tension" result and "cable section tension" result. "cable section tension" result give lower tension than "whole cable tension" result.
so which one should i choose for the analysis?

sorry about my english.
Thank you...

4. Joined: Apr 2011
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### CWTeebsAnomalyGenerator

Your english is fine man. I guess there's no universal answer to your question, but, as I said "whole cable tension" is basically the reaction at one of the end points (fairlead or anchor) for an installed system, and the reason it's higher is that it's the result of the cable section tension integrated about the length, including the weight of the cable. A conservative engineering analysis would just use whichever is higher, but it depends on the type of analysis you're doing. You can get these results using AQWA Cable dynamics, but if you're doing a stress/fatigue analysis, or just an analysis with an exotic mooring system, you have to use AQWA-TETHER, which I have not used extensively, but it outputs fatigue damage per day on the cable using rainflow counting and other statistical techniques, principal and Von Mises stresses in the element under the varying conditions, etc etc.

Last edited: May 26, 2012

5. Joined: May 2012
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### kojesJunior Member

thank you very much for your help....

I will be very happy if you help me again in the next time.

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