Aerohead's going to the wind tunnel! We're passing the hat to help with costs.

[aerohead]

I'm checked into the motel in Ogden,a little battle weary.
Yesterday,south of Montecello,Utah,driving in a strong,pure crosswind,I got popped by a Cd 1.04 Cattle-hauler.
We were closing at 130-mph and as I encountered the truck all hell broke loose.
The new front skirt was blown up,destroying the spring,bending the skirt/hinge into a vee,along with the roller bracket,tearing two sheetmetal screws out,and sending the roller to parts unknown.
I had 410 miles on the odo at the half-tank mark and was excited about the prospects for mpg.
I pulled into the first gas station to try and save the 'skirted' data.
She pulled 35.5 mpg at a max 65-mph through the mountains and high winds.
Since I left Denton 6-1/2 hours late,I went ahead and ran 75-mph with strong winds,grades,up to over 7,000 feet,returning 30.8 mpg.
From Montecello to south of Ogden I pulled another 35.5 mpg without the skirt,running a max. 65-mph through the mountains with winds all the way.
I tried to straighten the skirt last night in Green River,but I'm not sure that I can salvage it.
I'll work on it some more but I really need my 'shop.'
If I can't restore it we'll have smoke images for 'with' and '
without'.
No idea what it will mean to the Cd.(the trials and tribulations of the amateur aerodynamicist!)
There's a lot of bug juice to clean off the beast.
I got one side (drivers) 'complete' as far as the graphics go.It had a pretty good 50/50 look to it before the cows showed up.
Lots of camera action.Lots of wayside aero talks.A velomobile/EV biker from Pleasant,Texas put a $20 bill in my hand at a Dairy Queen in Chilicothe,TX.
Another guy,from College Station I visited with had seen BamZipPow's 1-wheel trailer rig and now he knows the rest of that story.
Gary gets in late afternoon.
Tomorrow should be a hoot.After 9-years,on-and-off with modding the T-100,there'll finally be some numbers to attach to it.All I need is the local air density,test air velocity,and drag force,and the Cd will fall out of the equation.
And the smoke flow imaging should reveal a lot.
I'll report in when I know something and can get online.
Am looking forward to enchiladas with Freebeard,and it will be fun to see Gary's reaction to Darko and Bonneville.
Thanks again to all the donors who've made this possible.Talk to you soon.

[Joggernot]

Dang. Do your best that's all we ask and it looks like you're gonna have a good time! I enjoyed Green River on a holiday a few years ago.

[BamZipPow]

That's sad that yer front skirt got blown up. Maybe we should name yer vehicle...Marilyn.

Pretty cool that someone out there actually saw my trailer and yer trailer. I wonder if he'll want to try one out, too!

Be safe out there, sir! If you need anything, don't hesitate to let us know!

[MetroMPG]

UPDATE: final tally as of Sept. 4th:

> Total collected: $1234.12 <

From 35 members. Thanks to everyone who chipped in!

[MetroMPG]

Just decided I'm throwing in another 44 cents so we can write a cheque for

$1234.56

[gone-ot]

Originally Posted by MetroMPG

Just decided I'm throwing in another 44 cents so we can write a cheque for

$1234.56

Obviously, someone is into NUMEROLOGY (ha,ha)!

[California98Civic]

Originally Posted by MetroMPG

Just decided I'm throwing in another 44 cents so we can write a cheque for

$1234.56

Huh. Stops at six... seems like seven ate nine.

[MetroMPG]

Tele Man... if that's my diagnosis, I'll take it.

California: ha!

[elhigh]

I picked a fantastic datum out of Phil's post:
"Since I left Denton 6-1/2 hours late,I went ahead and ran 75-mph with strong winds,grades,up to over 7,000 feet,returning 30.8 mpg"

Uphill, upwind, high speed, 30+mpg. Dang.

I'm not biting my nails over what the Cd is going to be, but only because I trimmed them today. This should be quite something.

[aerohead]

Wow! what a day!
With some wood and a tire hammer we were able to restore the skirt enough to run.
Doug was out of town and Tyler did the tunnel duty for us.(a really great guy!)
We started the session doing the smoke imaging.They use polypropylene,forced under air pressure up to the wand head,where the heating element flashes it into the smoke.
I ran the smoke while Gary used his Cannon digital camera on video mode.We used up a 2-Gb SD card for 15-minutes of recorded images.Airspeed started at 25-mph to guarantee a turbulent boundary layer.Later we increased the velocity during the last of the wake survey.
For the force measurements we ran the three 150-200hp air handlers at maximum for a 76-mph airspeed.
Run #1 indicated Cd 0.268.
Run #2 indicated Cd 0.267
Run #3 indicated Cd 0.251 (mirrors folded)
At 75-mph the mirrors are absorbing 1-hp (nasty!)
Front axle was -30-lbs downforce @ 130-mph (extrapolated )
Rear axle was +22-lbs lift @ 130-mph (extrapolated)
There is not a lot of contrast when viewing the smoke but I think everyone will be able to see everything okay.
I could see counterflow only behind the mirrors,tires,and tail truncation.
We spent only 2-hours so there's going to be a cash reserve for our next members trip to Ogden.
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We had all been discussing the CAR and DRIVER tunnel tests at the A2 Tunnel in North Carolina and Tyler was curious about what the numbers correlation between Darko and A2 might be.And since Gary had his 2010,Gen-3 Prius,Tyler said,what about throwing it in the tunnel for a comparison for free!
We juumped at the chance and after reconfiguring the load cell carriers we put Gary's car for a 76-mph run.
The Gen-3 came in at Cd 0.285.We can compare that figure with A2's number.
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So it looks like the T-100 is lower than the Prius,Insight-I and II,LEAF,VOLT,Corvette,and is close to the 1988 Opel Calibra,and not quite as clean as the Tesla-S.
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With a custom bed box which begins plan-taper just behind the cab,and provides tumblehome and radii, blending into the aeroshell,it should be easy to go below 0.20.
Smaller mirrors will help.(Tyler guestimates that a mirror delete would give Cd 0.24).
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We took the SD card to OFFICE MAX,I bought a thumb drive,and for $4 they transfered everything onto the drive,so both Gary and I have a copy of the images.
Tyler gave me a CD of the EXCELL Spreadsheet which has custom features for interpolation/extrapolation of the force measurements.
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Tomorrow we head for the salt flats.I'll continue to collect fuel data.
At Cd 0.267-268 she's at around a 39% drag reduction and it will be interesting to see what the aggregate mpg values look like.
According to Hucho's 30%/10% top speed relationship,it would predict the new top speed at 107.35-mph.I ran 108-mph back in 2007,with a little bit left,so I'm not sure about that.
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It's been a great day.Thanks again to all who got behind the project.When I get back,I'll get into the video stuff so we can get that into YOU-TUBE for all to see.
Let's get some more members to Darko!