Search found 7 matches

by TheoSchmidt
Sat May 14, 2022 7:27 am
Forum: Power craft & engines
Topic: solar electric propulsion of a power kat, 6.3 m
Replies: 16
Views: 35787

Re: solar electric propulsion of a power kat, 6.3 m

In http://web.archive.org/web/20200710010007/https://data.umwelteinsatz.ch/IBS/propsim.pdf I describe my own propeller simulation program and the large propeller I designed with it, using a Clark-Y flat-bottomed foil profile. The slip is very small at the best operating point. I'll try to compare th...
by TheoSchmidt
Thu Apr 28, 2022 7:18 pm
Forum: Power craft & engines
Topic: solar electric propulsion of a power kat, 6.3 m
Replies: 16
Views: 35787

Re: solar electric propulsion of a power kat, 6.3 m

OK, a one ton boat. Last year I did some model tests and calculations for a pretty basic 2.5 tonne catamaran, 7.5 m long with 0.75 m diameter cylindrical hulls, somewhat pointed at the ends (typical "party boat"). The total driving force was, up to 3.5 m/s, well approximated with the formula: Power ...
by TheoSchmidt
Sun Apr 24, 2022 6:44 pm
Forum: Power craft & engines
Topic: solar electric propulsion of a power kat, 6.3 m
Replies: 16
Views: 35787

Re: solar electric propulsion of a power kat, 6.3 m

Two 1.4 kW motors are surely ample for slow cruising. Alex has mentioned the importance of the thrust rating. This is so fighting a heavy headwind and of course you will then also be pounded by waves. For normal cruising the thrust figure isn't important, as you will simply get the speed at which th...
by TheoSchmidt
Tue Mar 29, 2022 6:55 pm
Forum: Forum Technical support
Topic: This Forum is functional again!
Replies: 2
Views: 7078

Re: This Forum is functional again!

Thank you, John! What I've done so far is to delete the category "News", which had few posts, after transferring these to "Events @ other announcements". Further suggestions welcome. Also, we have a number of "spambots" as users. The don't seem to be able to do any harm, but I aim to delete them. Ge...
by TheoSchmidt
Sun Mar 13, 2022 10:02 am
Forum: Technical Papers for review and comment
Topic: Ultimate Sailing for Oldies
Replies: 5
Views: 6271

Re: Ultimate Sailing for Oldies

Thanks to your getting me back into the loop, Roger, I'm able to reply to you here! Hence we have a need for superlift by pushing forward the A-frame control handle, effecting a larger angle of attack, and producing a lift co-efficient of 2.0. A “B” bar would be better, enabling the Aquaviator to pu...
by TheoSchmidt
Sun Mar 13, 2022 8:30 am
Forum: Wind- & Water-turbines, Propellors, Human power
Topic: Faster than the wind??
Replies: 2
Views: 5245

Re: Faster than the wind??

Two more links:
https://www.lockhaven.edu/%7Edsimanek/m ... dwfttw.htm "DDWFTTW Vehicle Analysis" by Donald Simanek 2013-2017
http://web.archive.org/web/201109040025 ... nd.org:80/ "Ride Like the Wind (only faster)" by Rick Cavallaro 2011