KMT

Hi John,

I have a problem with the result of KMT.
My results for a inland water vessel ( 135,0 x 11,44 x 3,90m) are :
T= 2,0 m
WL width = 11,400 m
WL length= 133,833 m
V = 2743,117 m3
VCB = 1,021 m
KMT = 2,541 m ! I think that`s wrong because:

KMT = VCB + IB/V with IB = B*B*B*L/12 = 7,044 m

What`s my mistake?

Best regards
Rüdiger Boost


KMT

Dear Rüdiger,

Please accept my apologies for the delay in replying. Just back from a holiday with no internet connection...

Can you posta copy of the model or email to me direct?

Many thanks

John

jamac
Site Admin
email - info_at_naval-architecture_dot_co_dot_uk


Hi Rüdiger, A quick chaser.

Hi Rüdiger,

A quick chaser. Did you get this solved? Please let me know if I can be of any further help.

Best Regards

John

jamac
Site Admin
email - info_at_naval-architecture_dot_co_dot_uk


KMT Bug

Hi there,

Not sure what you check first but heres a copy of my answer.


Dear Rudiger,

Apologies for the delay but I have had a chance to look at your model and
can comment as follows:

Appendage Achtrschiff STB
1. Has some unusual frames. Some discontinuities on the skeg (not smooth)
but this will not cause any issues with your results. Just a quality issue
with the model.
2. SPT20 at y=10m has a great hollow in it which would reduce the WP area.
have removed this although this may have been intentional.

Appendage Mittelschiff STB
1. All seems ok.

Appendage Vorschiff STB
1. Frame SPT 267 - 270 do not need offset at 0. Should not affect calcs but
removed anyway.
2. Frame SPT 269, there is a gap on the CL which needs to be removed. Offset
at x=0.00 and z=4.71 wrong and has the potential to introduce errors.

These are not the reason for the error however. It seems to do with the way
in which transverse inertia is being split for mirrored appendages. Will
need to look at this and issue a new version. Many thanks for bringing this
to my attention.

Also attached is the cleaned version of your model for your use.

Best Regards

John

Please keep an eye on the forums for more information.

Best Regards

John

jamac
Site Admin
email - info_at_naval-architecture_dot_co_dot_uk