"Michael Daly" ) writes:
On 28-May-2004, (William R. Watt) wrote:
An average person can sustain 1/20 horsepower. When a canoe or
kayak is powered by 1/20 hp in a dead calm the power is overcomimg
4 pounds of hull friction resistance and 0.05 pounds of hull wave
making resistance.
Where on earth do you get that breakdown? Friction resistance
80 times wave resistance?
"Winter's" data at hull speed and total resitance equal to 1/20 hp.
ie the data graphed on Winter's web site.
How can you make such a claim without any reference to the dimensions
of the kayak or canoe? Are you trying to suggest that my WW kayak
has the same resistance as my sea kayak?
as I have pointe out a number of times in this discussion that is
precisely the weakness in the data on Winters'w web site I would like to
see refined. DO YOU HAVE THAT DATA?
Mike wrote he thinks the friction and wave making resistance would
be equal. For that to happen the paddler would have to be
sustaining 1/5 horsepower, or 4 times as much.
Why? where do you get that number?
the data on Winters' webiste.
Athletes can do that. In short bursts athletes can produce 1/2 hp.
Cyclists can put out those kinds of power levels. However, if you're
not using your legs, horsepower is harder to generate. Elite paddlers
can put out about 0.3 hp. A fit recreational paddler can put out about
0.08 to 0.1 hp.
according to teh data on Winters' webiste you you have just
destroyed your earlier argument. at less than 1/20 hp the "boat" (canmoe
or kayak or whatever Winters' data represents) is harldy moving at all.
sorry, numbers don't lie. provided the numbers measure what we want and
I'm sure the numbers on Winters' website measure speed and hull resistance
of a paddled boat, although we don't know exaclty which paddled boat.
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