hydrostatics

I'm working on a project with freeship and had a question about hydrostatics

Its a fast planning hull 9'-11' ft,
what does the curve mean?
What would be the differences between the three hulls

Thanks
Ken

 

The curve looks like it might be your section area curve -- is your model in meters?

There's obviously lots of differences between the hulls. Can you ask a question showing a little more clearly what you want to know?

What's your purpose in designing these hulls?

 

That does appear to be the area curve and yes, there's huge difference between the profiles shown, but certianly not enough information about each, nor the SOR. Judging by the chine shape choices, I'd venture to guess Ken's hydrodynamic understanding of powerboat design is quite limited, possibly non-existent.

 

Agreed

My purpose for this project is to have a good planing hull, some of the plans/builds I have been following on other sites, and have issues with plowing or the chine not blocking spray coming over the bow.

It will be powered by a pwc engine & jet pump

So I am trying to address any issues on paper before it gets built and then try to correct hull issues.

I am looking for feedback on what looks ok and what needs to be changed.

Here is a screen shot of what I have so far.

Thanks
Ken

 

Without a reasonable grip on the physics and dynamics involved, how can you expect a semblance of success with a design? At the speeds you're likely anticipating, you need to nail the balance down good, as well as optimize the hull form, which requires more then a "what looks good" approach.

Simply put, you have to understand the issues, in order to correct them. I see a host of potential problems, with this particular set of shape choices and this says nothing about a weight study, appropriate centers locations, stability in all the axises, plus sufficient scantlings to accept the loads. You'd be best advised to get a set of plans and modify them to meet you aesthetic requirements.

 

Again thank for your time
I have purchased plans for the dynojet from glen-l,
so I have a good starting point for what I'm going to build.

As for reasonable grip on physics and dynamics, I do . But when asking for advise it usually
goes better to listen than brag about what you already know.

I will just follow and copy what everyone else is already doing,
http://www.nzjetboating.com/yabbse/index.php?board=9.0

Again that you for your time

 

Yes, it is a curve of immersed volume of the boat made by joining the measured area of each station with a fair line. When that volume is filled with water, it represents the displacement of the boat.

Good thing to start with an established boat plan and let that be your learning vehicle.