aerodynamics & 5th wheels

[AndyL]

Originally Posted by KamperBob

Andy, what do you know about that B&W tear drop photo?



I smell a good story.

BTW, I wasn't pushing generator use for you or anyone else. My point was gap filler. A cubby for gear? Chairs, grill, etc...

holman_norman [Tin Can Tourists Wiki]

There's the rest of the story about that picture - crap I can practically hear paul Harvey reading it...

[AndyL]

Its a damn good thing I'm not a professional tin basher...

Kinda grumpy with sore hands now... Pneumatic riveter puked on the third rivet- so by hand from that point on... thought I had set the front hoops angle so as to keep it within an inch of the cab... guess I knocked it and shifted things at some point...

Doesn't look too bad, did decide to run as a 12" deflector.


So here's what I have to fix:


I gotta see if I have some pool noodles around, those were good for a gap on the old truck camper...

[slowmover]

Looks good!!

[AndyL]

I'm still not quite happy with it... got a bunch of finishing to do, and this gap is driving me nutty, or should I say the 45° off the cab into a gap is making my head hurt... its close to 6" to span in places... duct tape isn't a solution I accept...

[KamperBob]

Originally Posted by AndyL

Its a '35 airstream torpedo, plan built airstream that just has a really sweet shape. the original plans have been posted in a few places now, although I'm not sure one would want to build them that way anymore...

(snip)

Kamperbob - yup following the theory, just have to pull out the cheech "we don't need no steeeeenkin" every now and then lol - other than a cooler I can't think of anything I'd want to put up there...

Thanks!

It's interesting that today's Basecamp model looks a LOT like a truncated version of the "original" teardrop. T@B came and went recently (and may rise again) with some noteworthy modernizations. But they got the nose wrong IMHO. Plan curvature was more useful inside with better aero outside. If only they Kammed the back and radiused edges for smooth recombination (instead of Vortex antagonisms) it would've been perfect. Still dang good, best in class, and far ahead of its time.

As for nose storage over the pin with a nose extension think stuff that folding chairs, dutch oven, BBQ grill & fuel, leveling blocks, wheel chocks, jack, tire iron, the spare tire maybe even, camp rake, small shovel, axe, bow saw, etc. It depends how you intend to use the trailer of course.

[KamperBob]

Originally Posted by AndyL

Its a damn good thing I'm not a professional tin basher...

Kinda grumpy with sore hands now... Pneumatic riveter puked on the third rivet- so by hand from that point on... thought I had set the front hoops angle so as to keep it within an inch of the cab... guess I knocked it and shifted things at some point...

Doesn't look too bad, did decide to run as a 12" deflector.


So here's what I have to fix:


I gotta see if I have some pool noodles around, those were good for a gap on the old truck camper...

That should help with aero. I haven't been ABA religious about mine I data correlation agrees with qualitative perception and theoretical basis.

Will the back side of your gap cap be open or closed? If open, swirl from separation bubble eddies reach inside as deep as they can. If you drive through rain it won't stay dry unless closed up. Closed requires engineering convenient access. It'll be interesting to see your solution and learn from your experience.

[AndyL]

The basecamp was supposed to be a throwback to the original, but I still like the original better... nevermind that the interior is pretty useless... its funny - every time I want something cool - I'm headed back to the 30s for inspiration.

I was planning to leave open, but it wouldn't be hard to slap a piece of poly carbonate on the back side - on a piano hinge for access...

Contemplating my way through a foam / fiberglass seal, want to grab so,e foam today for a drop in tonneau solution to test before we hit the road, but I have to go see if my RV roof reseal stood up to last nights thunderboomer first.

[AndyL]

Playing with flow illustrator and windtunnel 2d now... Seeing if there's anything else that can be tested...

Deflector definitely is better than a gap filler, at least in the theoretical world of CFD in 2D...

Been playing with a wing design - see if one of those oldschool wings like we used to have on vans & hatchbacks in the 80s makes a difference (kick some air down behind the RV) but looks like for it to be effective it'd have to be 16" over the back to catch some clean air...

Interesting pressure zones between truck & 5th, not sure if this is 2D effect or real...

[slowmover]

Interesting pressure zones between truck & 5th, not sure if this is 2D effect or real...

The "big truck rule" (as per KENWORTH) is that gaps between tractor and trailer of over 30" overcome aero aids such as spoilers. A closed gap -- preferably no more than 24" -- is where this "crosswind" begins to abate (and why I have a problem with the idea that a pickup pulling a conventional trailer is helped by a spoiler when the gap is generally four feet or more).

.

[AndyL]

Spent the day beating my head against an aluminium roof leak is still there, I just wish I could figure out where its coming from... water can't travel uphill can it?

I needs me a wind tunnel... this theory stuff sucks, I could be printing models on the reprap and be testing... all I'd need is a pressure sensor , anemometer and some humidity/pressure data...

In other words, my head hurts from trying to translate class 8 to RV