Read most of them and a few others. They all make some assumption that are not completely correct for my work. I am looking for a different kinds of data than they use and developed because of their assumptions about how propellers work and what is possible with propellers.
I like working with the folks that have tried different things and do not make assumptions, but talk about what they have see and tried, My experience is that everyone has some bit of the puzzle. I am here to listen to what the group thinks and has tries especially the little you wont believe this comments there is often a grain of truth in those comments that can makes all the difference. This group has already confirmed a few things in my mind and has started me thinking in another.
I once went to a week long creative problem solving course. In it we were taught that even the wild comment cam have merit. There was an exercise involving a Ping pong ball deep in a close fitting tube and the problem was to get it out with a short list of materials on hand. One person yelled "Piss on it" and was immediately dismissed. 3 hours later the best solution was to float it out, the Piss on it would have worked!
keeping an open mind and not making assumptions is most difficult but can lead to great things.
larry
--- In electricboats@
>
> Here's my summary of the discussion over the last few years.
>
> http://sites.
>
> -Keith
>
> --- In electricboats@
> >
> > this discussion sounds to me that regeneration has been discussed and even tried but seems to have been less successful than everyone would like. by this i mean pure regeneration not just matching the prop to sailing speed.
> > what happened and what are the reasons for not being successful.
> > how much drag for regeneration would be acceptable?
> > how much power needs to be supplied by the propeller to the motor to have regeneration?
> > what propeller rpm and torque would start and maintain regeneration.
> > How much power should be regenerated with time.
> > what usage? house batteries and power batteries of both etc.
> >
> >
> > --- In electricboats@
> > >
> > > I believe, but can't yet prove, that the one area where "regeneration" might actually be practical is in what Kevin P calls "electrosailing" - matching the prop rotation to the boat speed so that it's regenerating about 50% of the time (very low wattage mind you) The point of this is not really regen, but rather nullifying the prop drag and getting the extra 1/2 to 3/4 knot of speed. Over a sufficient distance, this extra speed is the practical equivalent of a feathering prop (without the drawbacks) and nearly net zero energy use.
> > >
> > > I currently have a 3-blade, so the above is more necessity than choice.
> > >
> > > -K
> > >
> > > --- In electricboats@
> > > > I bet a large diameter, high aspect ratio 2 blade prop would give excellent performance as a sail aux drive, especially if a method could be devised to lock the prop in the vertical position hiding in the wake of the skeg. A folding prop that would work in reverse would be even better.
> > > >
> > > > Denny Wolfe
> > > > www.wolfEboats.
> > > >
> > >
> >
>
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