Good morning everyone.

I wanted to indicate a method that could be useful to that naval modeller who wants to know the immersed volume of his model but does not want or cannot carry out the practical test in water.

Let me start by saying that I am convinced that the practical test in water is the best method to know the immersed volume and the displacement that the model will have once completed.

The products obtained by multiplying the distances between the immersed sections and the surfaces of the immersed sections must be added.

- IMMERSED SECTION AREA NR. (*) X DISTANCE TO THE NEXT SECTION +
- AREA ...
and so on.

To calculate the surfaces of the immersed sections, please read the link attached at the end of this message.

The more sections to include in the calculation, the more precise the estimate will be.

If you want an even more accurate estimate, introduce the half distances into the mathematical expression like this:


(section 1 x distance between section 1 and section 2 : 2) +
(section. 2 x distance between section 1 and section 2: 2) +

(section. 2 x distance between section 2 and section 3: 2) +
(section. 3 x distance between section 2 and section 3: 2) +

(section. 3 x distance between section 3 and section 4: 2) +
(section. 4 x distance between section 3 and section 4: 2) +

(section. 4 x distance between section 4 and section 5: 2) +
(section . 5 x distance between section 4 and section 5: 2)+

... and so on ... =


it is convenient to convert the result into dm3 because each dm3 of fresh water corresponds to one kilogram of weight.


If you are the designer of your model you should create equidistant sections (real or fictitious) to simplify the calculation.

If I wasn't clear or I need to edit part of this message due to inadvertent errors, please tell me.

https://model-boats.com/forum/131081