Centers of actions

[Alfred]

Hello everybody!
I bought end of 2005 Prolines 7. Now there is no longer support and I have some questions.
In Hydrostatic there are centers of actions
-Long Ctr. of float
In which connection I have to consider this point?

-Vertical CLP
-Longitudial CLP
How is the defination for this expressions?

[PI Design]

The Longitudinal Centre of Flotation (LCF) is the centroid of the waterplane area, ie the 'middle' of the shape of the hull outline at the waterline. This is the point about which the hull will rotate (although it will move as the boat heels and trims).

I'm not sure what CLP stands for.

[Wynand N]

Originally Posted by PI Design

I'm not sure what CLP stands for.

Center of Lateral Pressure sometimes also called CLR (Center of Lateral Resistance)

[PI Design]

Originally Posted by Wynand N

Center of Lateral Pressure sometimes also called CLR (Center of Lateral Resistance)

That what I thought, but how can you have a vertical CLP?That would be CVP?

[Alfred]

Thanks for the reply
To PI Design,
the following text is exactly the same as in Vacanti's Prolines 7
-Vertical CLP
-Longitudial CLP

Relating to 'Ctr of Float' I would think that this piont is a neutral value which isn't to place in a given position, in contrast to LCB and LCG which is placed in a certain relation to the design.

[PI Design]

The centre of flotation is useful to know, but not something that you would pre-determine. For a static, or pseudo-static, case it is in a fixed position, usually a little aft of the LCB. It can be used for trimming calcs.

I still think vertical CLP is a nonsense, but guess it means the depth below some datum point that the combined hull/keel/rudder lift force acts at.

[alpamis34]

You can figure out the location of vCLR and L CLR by doing some tests such as towing tank or CFD. The parameters that you need are the roll moments yaw moments and the Sideforce values.If you divide the roll moment by the Side force you will obtain vertical position and with the yaw moment division you get the horizontal position.

[Alfred]

Thanks for reply
V CLR and L CLR are certain points in Prolines 7
Wifh your replys I can use this values.