Propeller for HPV

[sarathes]

Hai,

My team is on to a project of designing a human powered vessel for my university team competition. The hull is decided to a hydrofoil attached catamaran type to ply at 14 knots. But I have no idea, what kind of propeller to be used for attaining this speed and what is the criteria for selecting the propeller. If anybody can help me with the problem, I shall be highly greatful.........

Sarath

[DaveB]

Originally Posted by sarathes

Hai,

My team is on to a project of designing a human powered vessel for my university team competition. The hull is decided to a hydrofoil attached catamaran type to ply at 14 knots. But I have no idea, what kind of propeller to be used for attaining this speed and what is the criteria for selecting the propeller. If anybody can help me with the problem, I shall be highly greatful.........

Sarath

Depending on the rules of the competition an air-prop might be beneficial... another university team used an air prop and there are rumours that they may have benefitted from a tailwind during trials/races... Good luck with it...

Dave

[sarathes]

Thanks for your reply.....I look forward to it........

[gonzo]

Propeller design, regardless of application, revolves around available power. Depending on who is pedaling it will vary.

[sarathes]

The expected power for two persons for the design is one HP. I presume to get a rough idea of the propeller to be used....If you can help me in this regard, its highly appreciated

[tspeer]

You need to do some basic calculations of thrust and power using momentum theory. That will help size the prop diameter and determine the advance ratio (ratio of forward speed to prop rotational tip speed). Ideally, you'd have propellor charts to work with to pick the pitch and diameter that give you the highest efficiency at the speeds you're considering.

As a practical matter, you might look at model airplane props. They are about the right size for a HPV, and come in a variety of pitches and diameters. You're going to have to optimize the prop experimentally no matter what you do, so you might as well buy a number of props that bracket the most logical range of design parameters and just see what works best.

[boogie]

hi there,

you might want to check these guys out:
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cheers
boogie