Hello group. I know we are a small group but it is inevitable that this industry is going
to grow fast. Any cool projects or ideas?
What does the group need ? i have been doing wings for years and years, real wings..... NACA formula's etc
Hi Kris and Brian. Sorry for my absence. I created this group because I think more hydrofoil concepts are needed throughout various industry segments. It needs to become more widely spread and more widely known (about).
I am an engineer and have a PhD in engineering physics and I specialized in wave energy. Even a few wave energy concepts are based on various arrangements of foils - from vertical axis hybrid wave and tidal devices to pure rotating turbines and oscillating foils. There are also a few fin drive concepts around which I find extremely interesting. Hobie kayaks with the Mirage Drive is one. Dolprop is another one.
But in particular, on my on part, I have started developing a new foiling wind turbine concept for which I am seeking development support here in Sweden. If this group could help out on that, I'd be very happy since I am pursuing this alone as of now. I'll have a master student helping me this fall - by doing CFD simulations on the submerged (foiling) parts of the turbine. The design of the foil system is yet to be detailed. But we will test various configurations. The concept development is in a very early stage as you may understand.
At present I am also (on one of the jobs) leading a proposal submission for the development of an energy efficient electric catamaran.
I have an idea i could use a little help with, i have no cad skills and do not own a 3d printer. I am avid fisherman and have an idea about a lure+foil, currently im trying to find someone to print me a foil just like whats used on boards but, to scale. I could play around with attaching to lures via molding resin. there is a file i see on here that looks like it would work for me, how can i get one printed out?
Hi Rob. Please elaborate. You mean a lure as in a bait for fishing? There should be lots of places for 3D-printin on demand (I don't know where you are located), but then you need to supply a 3D CAD-file for them. I'm sure there is someone in the Grabcad community that could draw one for you but maybe it's not for the hydrofoil group?
To add, if it's a tiny foil you are looking for, I would suggest you carve one from hardwood to start evaluating your design.
yes fishing, I thought because it is a hyddo foil i was in the right place. I was thinking of doing that with clay then molding into resin, my concern is not being an engineer getting the proportions right so i can actually achieve lift
Ok, then I understand. But what is the actual purpose of the foil? The bait is not necessarily heavier than water? So why do you need lift in the first place? But if you need lift, any airfoil profile at some angle of attack will give you lift. Even a flat plate gives you lift if it si at some angle of attack. A simple NACA profile is however often a good start. Have a look at http://airfoiltools.com/airfoil/naca4digit for tabulated values of profiles. I have printed profiles on paper and used foam-cutting with good results. Cover with glass fibre and epoxy resin and there is your relatively well-defined profile. What is the final physical size you want?
Not sure what you mean. The group pic is my own wakefoil prototype.
This is a project I have been working on for a year now. It can attach to a Surfboard, Paddle board, Kayak. 350 Watts 20 Ah 36 volt Lipo Propeller. Still working on improvements but have had lots of fun with it so far.
Oh got it there is a company in Florida where they only sell the foil parts that use a similar material then once you pick the parts out they ship it and you have to assemble it yourself.
Well, I haven't even tried this one yet. I'm building a wakeboard to go with it. The foil is made of wood and its epoxy/fiberglass covered.
Getting close to point where I can start selling it. It is a lot harder than I expected especially when water is introduced. The torque/speed is not the issue its keeping everything working consistently has been the main challenge.
I am going to weight the lure body so its in and out of the water almost skipping, while trolling, speed tends to vary slightly, so as I slow it sinks down, speed up it planes out just above the water. the body 6-8 inches so i figured a foil of 3-4 half the size of bait. I will check out that resource, and thank you for the foam idea that i think will work best to get a initial form to start experimenting. I am trying to mimic flying fish, i have been watching videos of fish going after flying fish as they break the surface, which makes for some great action. As any fishermen will tell you top water action is where the excitement is Your help is appreciated
this is a great tool, one more question any characteristics that are more beneficial in the water as opposed to air
Not to start with. On the fluid though, water is 800 times heavier than air so at the same speed the same foil will produce 800 times more lift, so a the foil can be made small. Also consider working with small angles of attack in water (risk of cavitation). In air you can sustain much larger angles.
Sure! If you haven’t looked at ROV thruster design, I am sure you could get good ideas from there. Molding the motor in resin, putting a slider plastic (composite) bearing in the motor’s airgap and let the motor be flooded (and thus directly water cooled) is another approach. Do you seal it off the ”conventional way”?
Hi Magnus Rahm,
your group arouses much interest in me. In particular I would like to develop an animated 3D model of Dolprop (overly innovative). I would like to help you in your Swedish project but tell me how ... I am a technical illustrator and I have good practice in 3D modeling. I am currently unemployed and unfortunately I have a lot of time at my disposal.
Am I good at calculations and in physics but will they be enough for your project? In any case let me know how I can help you or be useful to this group! I wish you good luck for your business!