National Competition,Trimaran KMN Freyr design

[ScienceGreaker]

Hello,we are group of three 16 year teens. We are in the middle of the process of designing and building a trimaran boat.

• The model should be made in scale 1:100 of 90m long ship(total length), so it shouldn't be longer than 90cm.
• The boat should be made out of polystyrene.
• Model should be designed with a hull.
• It should transport a load of a total 3 kg water, spread into 6 juice boxes. The boxes should be placed on the deck and simulate containers on the real ship. The deck should be above the waterline.
• It should be equipped with 3 kg ballast, in form of a metal plate on the hull bottom.
• Powered by an electric battery, engine and propeller.

We are inspired by the USS independence boat and we are using delftship to design our boat.

The boat is going to be tested in speed,stability and design.



It would be very kind of you if you could take a look at our design and help us a bit on our way.

Questions are welcomed.

Thanks

[peterAustralia]

makes it very hard when you have saved your image as an fbm file

am i correct, the file is a fuzzy bitmap image?

Suggest opening it on your computer, press printscreen, the go to paint and save it as a jpg or something. I really cant be stuffed searching the internet to find a program just to open a single file.

[ScienceGreaker]

Hello, it is a delftship design not an image. You will have to use delftship to open it. I can provide some images of the differences views later today when I get back to my working machine.

[Submarine Tom]

ScienceGreaker,

Great idea, great project.

Post lots of pictures and let us track your progress.

-Tom

P.S. Your image was already showing when I opened your thread, no problem.

[Leo Lazauskas]

If you want to get the best speed out of such a small model, you might have to design it for laminar flow.

[messabout]

You have an interesting project worthy of our collective attention. Shall we presume that this is a school assignment?

At first thought, the total displacement requirement may become problematic because of the 90cm length of the model. The hull sections may need to be fatter than you would like, in order to support the assigned weight. You might need to consider a planform other than the Enterprise. All this is subject to discussion and probable argument from the forum members.

You have already attracted some exceptionally qualified respondents. Disclaimer: I am not one of those, just an interested old guy who is a veteran model builder.

Go for it and stay in contact with us.

[ScienceGreaker]

Just to clear this out this is a school project in which the whole class competes within itself and the best of the class advances into the national competition which will take place at NTNU (the whole contest is also just an advertisment for NTNU )

Tom: Of course I will post lots of pictures and track our progress the boat will be finished 7th of march. I am the one responsible for writing the report and gather information.

Leo: You got any good ideas how to make the best possible laminar flow?( I will edit some pictures from our model into this post later if you need them)

Messabout: This will be taken into account, but we will of course do the neccesary calculations before we begin building so it doesn't sink with the ballast and cargo on it

Some measurements:


• LOA = 90 cm
• Height = 14,5 cm
• BOA = 29 cm

[ScienceGreaker]

Perspective view

Body plan

[peterAustralia]

very nice shape

glad I dont have to make it, but very well done

If it was a real cargo ship, the center hull would have a more rounded bottom to reduce wetted surface area and hence skin friction. Also having a rounder bottom would allow it to work in that much shallower areas. The deep center hull would reduce slamming and give a good ride in a seaway.

Overall, that is very very nicely done