How to fix leakpoint problem in FreeShip?

Hi everyone, I am designing a canoe to be used in the ASCE Concrete Canoe Competition. As I finalize the design, I am encountering an error with the leakpoint. FreeShip states that I have a leakpoint below the DWL and I am unable to perform hydrostatic calculations because of this. I am fairly new to this software and I am not sure how to proceed. Any and all help is welcome!

I have attached my file if anyone would like to take a look.

 

Cristian,

there is a leak in the bow area above the upper chine; i.e. no "watertight" connection to the top sides here.

I moved one control point forward so one can see the issue more clearly:



Also there are two separate control points aft where the two chines meet - that's maybe no problem for the hydrostatics calculation, but a bit "messy" in my opinion.

I've fixed your model; please find it attached.

Hope this helps.

 

Hi Olav,

Sorry for the late response! I assumed I would have received an email notification about a reply as I am new to this forum.

Thank you so much for looking into this for me and helping me see the problem. I opened the file and am still unable to get the output for the resistance. Doing my own calculations, I estimated the draft to be 0.655 feet. Does the resistance output work on yours using this draft?

 

Never mind, Cristian.

Sorry, I didn't check for the resistance calculation when having a look at your model; the only objective was to search for the leak and to get the hydrostatics calculation to work.

Now I tried to perform a resistance estimation using the KAPER method - with your design draught of 0.655 ft the prismatic coefficient cp is outside the valid range for this method and Delftship refuses to do any calculations. I tried a second time with a somewhat reduced draught to get cp a bit lower - et voilà, it worked! This means that the model itself is fine, it just doesn't fit into the envelope of this particular resistance estimation method.

My advice is to go and use Michlet instead (there's lots of info on this forum; just use the search function) which should be well suited for your narrow canoe hull. Freeship can export the hull geometry to Michlet.

 

Olav,

No worries! I appreciate the favor nonetheless.

I will become more familiar with Michlet and hope to obtain the results soon. Thank you again for your help!

Best,
Cristian