I would be curious to see the pressure plots with actual assymetric wing forms (say eppler 420 assymetric wings) on both the jib and the main, vs just flat sails, in a similar sail placement. Taking into account both your forward motion (say ten mph) combined with the natural wind (sailing into the wind, say 15-20 degees off the natural wind), so the combined apparent wind is around 20 mph, (basically the wind on your face so to speak), with an angle of attack on the wings of around 15 degrees off the wind.
I have no clue how to plot something like that.
Basically what I'm describing is my next planned wing sail design, which is designed but not built yet. The wing jib is done, (I've been using the wing jib about 3yrs now), but I haven't built the main wing yet, I have all the main wing sail material purchased (about a $150 bucks in material), but stopped construction because It's beyond my math skills to actually figure it out and I can't get any of the programs I have access to, ( ie... sailflow, etc) to give me any useful information, (must be too complex for the software apparently), I suspect because of the forward motion (8-10mph from my motors and peddle drives) seems to throw everything into a tizzy.
Basically the setup you show in your plot looks very similar to the setup I've been running for quite a while now, ( if you switched out the single layer foresail with an eppler 420 assymetric wingform (my wing is around 5-6" thick, the actual length to width ratio is 12%, ( the math... 4ft times 12% equals around 5.75" thick), and the angle of attack on the wing is around 10 degrees.
I suspect I'll actually need to build the darn thing, then try it out, simply because the math is way beyond my understanding and math skills. All the stuff I'm currently doing is roughly based on information from Tom Speers web site, (
http://www.tspeer.com), the stuff he published about wing sails.
Since my sails aren't used for primary propulsion, it really doesn't matter to me what the performance is on other points of sail, (ie.. reach, downwind, etc), because the positional relationship ( orientation) of the jib to the main is fixed and only works upwind in a narrow performance window (5 to 20 degrees off the wind), on all other points of sail the sails revert back to old fashion sailing theory.
I don't expect anyone to do the math for me, I'm just describing the brickwall I ran into (understanding wise), I suspect nobody has tried to go down this road before, and I'll just need to muddle thru it trial and error, (again, (lol)).
Obviously my ultimate goal is 15mph upwind ( really close reach), in 5mph natural wind (3x windspeed), and get at least 100 mpg with the hybrid gas engines, that will eventually be replaced with solar/battery, electrics. Obviously I'm not their yet, ( my current system is only 1.5-2x windspeed, and between 60 and 80 mpg), still have a long way to go.
FE
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