Is there any hope? - Page 2 - Fuelly Forums

Android Users - Coming Soon! - Migrating from aCar 4.8 to 5.0

Reply
 
Thread Tools Display Modes
 
Old 03-28-2007, 09:51 PM   #11
Registered Member
 
Join Date: Nov 2006
Posts: 358
Country: United States
I just did a search for aerodynamic trucks and RV's, and found a few things that you might want to look into adding.

http://images.google.com/imgres?imgu...US203%26sa%3DG

http://images.google.com/imgres?imgu...US203%26sa%3DG

http://images.google.com/imgres?imgu...US203%26sa%3DG

http://images.google.com/imgres?imgu...US203%26sa%3DG
__________________

repete86 is offline   Reply With Quote
Old 03-28-2007, 09:55 PM   #12
Registered Member
 
Peakster's Avatar
 
Join Date: Sep 2006
Posts: 467
Country: United States
Attachment 303

That's quite the 'spoiler' that rig has there. I still don't understand how spoiler's are supposed to reduce drag. Wouldn't it just be more frontal area for air to hit?
Attached Images
 
__________________

Peakster is offline   Reply With Quote
Old 03-28-2007, 10:01 PM   #13
Registered Member
 
Join Date: Nov 2006
Posts: 20
Country: United States
Quote:
Originally Posted by cfg83 View Post
Hello -

Someone else posted this somewhere else in GasSavers :

http://www.dfrc.nasa.gov/Gallery/pho...L/E-38096.html
Attachment 302

But what are all those "hairs" for ?

CarloSW2

Thats hilarious!

I'll get right on building that huge tail cone! The wife will love it.

Thanks

Peter
__________________
83 Mitsubishi Mighty Max
pmistel is offline   Reply With Quote
Old 03-28-2007, 10:02 PM   #14
Registered Member
 
Join Date: Nov 2006
Posts: 358
Country: United States
I imagine that it acts as a large vortex generator that makes the low pressure area in the back a little smoother.

That one was designed at Georgia Tech, so I assume that the kids there put it on for a reason other than looking cool.
repete86 is offline   Reply With Quote
Old 03-28-2007, 10:26 PM   #15
Registered Member
 
The Toecutter's Avatar
 
Join Date: Mar 2006
Posts: 612
Country: United States
Send a message via AIM to The Toecutter
Quote:
But what are all those "hairs" for ?
Tuft testing. If you can get photos of the vehicle moving with pieces of yarn taped to it, you can see where turbulence are being generated.

This allows you to make modifications where there is turbulence, so that you're not doing it blindly.



Next to a wind tunnel, it's the best you'll get.
The Toecutter is offline   Reply With Quote
Old 03-29-2007, 02:34 AM   #16
Team GasMisers5!
 
landspeed's Avatar
 
Join Date: Nov 2006
Posts: 440
Country: United States
As noted above, a lot of things could be done to improve the MPG .

Rolling resistance is going to be high due to the weight of the RV, so, see if you can get lower rolling resistance tyres, and pump them up a bit more (but, not crazy-high as some of the cars on here, as you don't want to blow one of them on a vehicle that size).

Front (if they wheels on full lock don't protrude from the wheel arch) and rear wheel skirts will also help, as will a full belly pan. These would have to be removable, at least in the areas where you need to change wheels and tyres.

Finally, the cone mentioned above is a good idea - if you had enough time you could design a cone shaped attachment at the back, which if made well enough, could even be used to store (lightweight) items while you are travelling around e.g. spare bedding and the like.

With the above mods, which won't really affect the appearance (apart from the cone, but, if done well, this would not look odd at all - you could have a 'square cone', to more closely match the style of the vehicle), you should get a big improvement in MPG!.

You could also try the trick of disconnecting the fuel lines (after depressurising them), and having a small container of diesel. Idle the RV on that, and see how long it takes to drain it, then work out the fuel consumption at idle. If it is very low, then you can engine-on coast whenever possible, to save fuel that way, and reach the top of hills at 20mph (if not holding up traffic), so you can then roll back down the hill and be at 60 by the bottom of the hill - that RV will have a lot of momentum for this kind of driving!
__________________

Team GasMisers5 - #1 for first three rounds of the original GS Fuel Economy Challenge
Miles displaced by e-bike since 1 Jan 2008: 62.6 (0 kWh used)
Hypomiler
landspeed is offline   Reply With Quote
Old 03-29-2007, 02:36 AM   #17
Team GasMisers5!
 
landspeed's Avatar
 
Join Date: Nov 2006
Posts: 440
Country: United States
Mmmm. How about fitting a larger front bumper (not freakishly large) so that a lot more air flows over the vehicle rather than under - this should make a difference surely?
__________________

Team GasMisers5 - #1 for first three rounds of the original GS Fuel Economy Challenge
Miles displaced by e-bike since 1 Jan 2008: 62.6 (0 kWh used)
Hypomiler
landspeed is offline   Reply With Quote
Old 03-29-2007, 06:22 AM   #18
Registered Member
 
Join Date: Oct 2005
Posts: 1,978
Country: United States
Swift Trucking

The first thing that came to mind is a rounded cone design that I've seen on the side-load, tractor-trailer rigs:



The green cone should help finish the air, and is probably a commonly available product that could be cut/customized, if you don't need that area back there (or hook-up a swinging hinge to open it up).

"Swift" Trucking Company uses these (usually white) on their side-loaders. They also have a 61mph governor on their tractors, so they're usually looking for ways to save fuel. They're currently working with the EPA in other testing. Look for these on the road.

Of course the next simplest thing to do is keep the speed as close to 55 as possible. On long trips that might mean a significant time distance to the destination, but it's not being there, it's getting there, right?

RH77
__________________
rh77 is offline   Reply With Quote
Old 03-29-2007, 07:42 AM   #19
Supporting Member
 
cfg83's Avatar
 
Join Date: Sep 2006
Posts: 1,779
Country: United States
repete86 -

Quote:
Originally Posted by repete86 View Post
I really like this last URL you posted because of the massive rear-wheel mod.

Attachment 304

CarloSW2
Attached Images
 
__________________
Old School SW2 EPA ... New School Civic EPA :

What's your EPA MPG? http://www.fueleconomy.gov/feg/calculatorSelectYear.jsp
cfg83 is offline   Reply With Quote
Old 03-29-2007, 09:52 AM   #20
Registered Member
 
Join Date: Nov 2006
Posts: 20
Country: United States
Great suggestions, But obviously I was kidding about building the rear cone. Here is another shot, it may be 15 years old but still in good shape so I can't turn it into a Franken-car (franken-rv?)

Can't cover the tiger!

Thanks

Peter
Attached Images
 
__________________

__________________
83 Mitsubishi Mighty Max
pmistel is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Can't Retire eudy Fuelly Web Support and Community News 8 01-10-2012 10:28 PM
MPG not calculating ncdoak Fuelly Web Support and Community News 1 11-18-2011 05:22 AM
Fuel Cost MHM Fuelly Web Support and Community News 1 07-26-2009 12:18 AM
Sort by Number of Fuel Ups ebchu Fuelly Web Support and Community News 7 10-27-2008 05:36 AM
The mobile site default date is behind by 1 month and one day on Opera Mobile 8.65 mkizer Fuelly Web Support and Community News 2 09-15-2008 03:58 AM

Powered by vBadvanced CMPS v3.2.3


All times are GMT -8. The time now is 09:49 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.