US87891
Posts: 195
Joined: 1/2/2011 Status: offline
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quote:
ORIGINAL: Buck Beach After that will you work on creating AVGas for our planes, they just don't run right on carrots and potatoes? OK so much for dreaming. Buck Wish we could. Gonna have to think of green gas from rutabagas. The last email I got, after J was talking to the usual historical suspects. I don't know how to post up the graphs, but I assume people like JuanG will know what's going on; quote:
Ok, the burn/HP/Hr is in the same ballpark for design ‘cruising’ speeds for most displacement vessels. For merchant vessels, the design ‘cruising’ speed was determined for shaft revolutions at approximately 87-93% of power settings. For warships, the design ‘cruising’ speed was determined at the cusp of the second derivative of the burn/HP/Hr curve, derived from design data. The burn rate, after the cusp still follows the cube law, with an adjustment function depending on the Hp/Dspl ratio and the root-speed equations. The different colors in the graphs are calibrated to the major ship coefficients. I’m sure you know that Lwl/Bwl has a direct first order effect on resistance (drag) and Draft/Bwl has an inverse first order effect on waterplane resistance. So holding all other things equal, I’m seeing fuel burn rates, in terms of Lbs/HP/Hr that are totally, internally, self-consistent. Damn, I love it when the math comes together. As you can see, everything fits on the curve. So I’ll be tweaking things to get them righteous. I’ll keep the Fuel Cap where it is and only tweak endurance so it updates without issues. I think it represents a 15% increased fuel use across the various ships. Let me know wha happens. Btw, Janet was cutting her grass, at 2:00pm, in the middle of the Alabama heat wave, so for a joke I tell her I’ll give her $20 to cut mine. She’s a school teacher so she knows all the local bite me things and prolly said most of them. But come Tuesday, Graham is knocking on the door lookin for some gas money, How could I resist? Did a good job.
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