08-03-2015, 02:35 AM
|
#1 (permalink)
|
EcoModding Jack
Join Date: Nov 2010
Location: Sacramento
Posts: 335
Thanks: 12
Thanked 58 Times in 40 Posts
|
Why there isn't an aerodynamic shaped RV
They are all rectangle boxes, really about the worst they can be.
Living/Storage space is highest on the priority list, and tops the efficiency,
so a rectangle is going to give the most space.
Lots of disussion about streamlining an RV, has anyone actually done it and how much efficiency improvement do you get after losing all the space?
I'm looking at 33ft motorhome with some rear side damage, and the back 24ft body could be totally redone.
I'm thinking the easiest most cost-effective way is to make the roof pop-up hinged on the front section, so it hinges down to give a nice slope while driving, and hinges up to give a big roofline and living space inside.
I'm planning to use for storage really, but if I rebuild the rear section, might be interesting to see how efficient I could make it while still having lots of storage space when hinged up.
|
|
|
Today
|
|
|
Other popular topics in this forum...
|
|
|
08-03-2015, 03:07 AM
|
#2 (permalink)
|
Not Doug
Join Date: Jun 2012
Location: Show Low, AZ
Posts: 12,241
Thanks: 7,254
Thanked 2,234 Times in 1,724 Posts
|
The Toyota Prius is popular, but it seems like many people purchase it for the smug superiority, while other cars are slowly trying to sneak in aerodynamic tweaks, like tapered cabins. I would be kind of surprised if you could not find an RV with some tapering, but I think there is a big difference between head and shoulder room and being able to walk around inside, store things in cabinets, etc.
People seem to think that actual aerodynamics are ugly, but it could just be that if you can afford an RV, you can afford to haul around a box.
If you found a superficially-totaled PriusV, could you turn it into an RV?
|
|
|
08-03-2015, 10:35 AM
|
#3 (permalink)
|
Master EcoModder
Join Date: Oct 2011
Location: ellington, ct
Posts: 830
Thanks: 44
Thanked 104 Times in 80 Posts
|
Prius is not really big enough.
I would like to see a minivan sized RV camper.
Make it 4 cylinder fwd and add a rear hybrid drive. The beauty of such a system would be good performance/efficiency as well as a nice sized battery pack that could easily run the AC/misc electrics while parked for hours without a noisy generator
|
|
|
08-03-2015, 12:00 PM
|
#4 (permalink)
|
Rat Racer
Join Date: May 2011
Location: Route 16
Posts: 4,150
Thanks: 1,784
Thanked 1,922 Times in 1,246 Posts
|
You don't buy an RV for the driving characteristics.
__________________
Quote:
Originally Posted by sheepdog44
Transmission type Efficiency
Manual neutral engine off.100% @∞MPG <----- Fun Fact.
Manual 1:1 gear ratio .......98%
CVT belt ............................88%
Automatic .........................86%
|
|
|
|
08-03-2015, 02:13 PM
|
#5 (permalink)
|
Ultimate Fail
Join Date: Feb 2008
Location: Austin,Texas
Posts: 3,585
Thanks: 2,872
Thanked 1,121 Times in 679 Posts
|
There are a couple of members here that have done aeromods to their RV.
As others would say " It's fruit ripe for the picking".
I think of it this way : the worse off something is aerodynamically, the more easily you will see a noticeable change when doing aero mods.
|
|
|
08-03-2015, 06:58 PM
|
#6 (permalink)
|
Master EcoModder
Join Date: Jun 2008
Location: Utah
Posts: 975
Thanks: 193
Thanked 312 Times in 221 Posts
|
A boat tail is a mod that should make a big difference while not impacting interior space. This one increased mileage from 13MPG to 16 MPG according to preliminary tests.
|
|
|
08-03-2015, 10:06 PM
|
#7 (permalink)
|
Master EcoModder
Join Date: Aug 2012
Location: northwest of normal
Posts: 28,728
Thanks: 8,155
Thanked 8,937 Times in 7,379 Posts
|
Quote:
They are all rectangle boxes, really about the worst they can be.
Living/Storage space is highest on the priority list, and tops the efficiency,
so a rectangle is going to give the most space.
|
I see it from the other side, call it an 'obversation', an aerodynamic shell with the same drag as that little box would be immense. As a vehicle, it has legally defined length, width and height — a box. An ideal dwelling will be a circle.
This 33-footer, is it a class A- or class C-motorhome? Would you be willing to extend the length (and licensing cost) to increase the fineness ratio?
Consider all the side taper you can pull off, with a flat roof. If it has a radiused edge to avoid vortex generation wouldn't a Tropfenwagen shape give space without needing pop-up/outs.
|
|
|
08-04-2015, 03:00 PM
|
#8 (permalink)
|
EcoModding Lurker
Join Date: Mar 2015
Location: -
Posts: 30
Thanks: 3
Thanked 12 Times in 11 Posts
|
Last edited by gafhj; 08-04-2015 at 03:31 PM..
|
|
|
08-05-2015, 01:24 AM
|
#9 (permalink)
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,923
Thanks: 0
Thanked 1,697 Times in 1,515 Posts
|
Unfortunately, advanced aerodynamics wouldn't improve the space-savings in a motorhome so much as a boxy layout does. There is always some compromise. Anyway, I would eventually consider a platform with the engine closer to the driven axle such as the FWD Ram ProMaster in order to get a lower floor, since it would lead to an improved internal height even if the external height get lower than a comparable front-engined RWD van.
|
|
|
08-05-2015, 03:02 PM
|
#10 (permalink)
|
Master EcoModder
Join Date: Aug 2012
Location: northwest of normal
Posts: 28,728
Thanks: 8,155
Thanked 8,937 Times in 7,379 Posts
|
Here is the front wheel drive motor home I had. Sold because I lost my parking space.
It was 18.5ft long. Here is a proposal for a new body with the same drivetrain.
At a fineness ration of 4:1, it would be 32ft long; with similar interior volume but 50% higher licensing fees. But it would have gone from worst to best case for aerodynamics.
The Clark is gone, but I still have a Lexus motor-generator* that could power an electric version about the size of a Dodge van or VW microbus. So it still could be built.
Edit: *Now that I think about it, the folks at EVTV are reverse engineering the Tesla drivetrain CAN Bus messaging. That would be an appropriate size for a motor home, about 400hp.
Last edited by freebeard; 08-05-2015 at 03:43 PM..
|
|
|
|