air currents

[bike4mee]

In four wheel camper owners FB site Steve Fox posted this interesting computer sim. Looks like the air from the windshield actually may deflect some of the wind force that goes into that dead space above the roof, causing drag. Just a thought
Is it worth it to put wind deflectors on the roof? Anybody actually save gas mileage

 

[yovik]

In four wheel camper owners FB site Steve Fox posted this interesting computer sim. Looks like the air from the windshield actually may deflect some of the wind force that goes into that dead space above the roof, causing drag. Just a thought
Is it worth it to put wind deflectors on the roof? Anybody actually save gas mileage

I'd like to see that simulation on the back of the camper, where there's a significant bit of drag as well. I think I read somewhere that it's a bigger mileage detractor that the dead space is.

Also, I have a smallish Yakima wind deflector on the cab of the truck and one on my front Yakima bar on the roof of the 4WC. Results: no significant changes to my mileage. Others have reported similarly I believe.

Again, I wonder about the sharp edges at the back of the camper at least as much as those leading edges. I see a fair number of semi trailers with very sizeable deflectors on the rear end.

(Photo from Thursday, July 26, 2018 south of Crested Butte, CO)

 

[Old Crow]

I'd like to see that simulation on the back of the camper, where there's a significant bit of drag as well. I think I read somewhere that it's a bigger mileage detractor that the dead space is.

Also, I have a smallish Yakima wind deflector on the cab of the truck and one on my front Yakima bar on the roof of the 4WC. Results: no significant changes to my mileage. Others have reported similarly I believe.

Again, I wonder about the sharp edges at the back of the camper at least as much as those leading edges. I see a fair number of semi trailers with very sizeable deflectors on the rear end.

On the subject of semi-trailer deflectors ....

Stemco's version (there are several manufacturers of trailer tails)

And their automatic one... wandering the west!

Interesting stuff. And simple enough in concept to make us start wondering whether something like this would be possible (or worthwhile). This article says the 6% fuel savings at 65mph (on a big-rig) means a payback of two years on a $2000 investment (in 2011). The Stemco automatic video (above) says 1.1 liter savings per 100km.

.

 

[Old Crow]

Old-school approach to seeing air currents.... string, tape, and slo-mo camera.

 

[Chrish]

I've been doing a lot of reading on all things truck camper lately and from what I've been reading there seems to be a reported 1 mile per gallon improvement when using those truck roof wind deflectors for four wheel camper type pop-ups.

 

[Vic Harder]

dunno about mpg, but the noise difference is astounding

And there are older threads on this forum about wind deflectors/fairings
http://www.wanderthewest.com/forum/topic/9879-wind-deflectors/
http://www.wanderthewest.com/forum/topic/11649-new-fwc-camper-wind-fairing-suggestions/
http://www.wanderthewest.com/forum/topic/6020-wind-fairingdeflector/

 

[slomo]

can't vouch for mileage savings but lowered noise level.

 

[ckent323]

slomo,

What brand and model of cargo basket is that on the roof oft the truck cab? I am looking for one like that.

Thanks,
Craig

 

[SLEDAWG]

Has anyone tried AIRTABs and seen a MPG improvement?

www.airtab.com

 

[rubberlegs]

In four wheel camper owners FB site Steve Fox posted this interesting computer sim. Looks like the air from the windshield actually may deflect some of the wind force that goes into that dead space above the roof, causing drag. Just a thought
Is it worth it to put wind deflectors on the roof? Anybody actually save gas mileage

I got a drag of 63 instead of 65 with a faked in wind deflector. But the picture is crude and would like to try better when I get time.

 

[Roaming_Eagle]

The gap between an eagle and tacoma was horrible, visually speaking. But by adding a wind deflector it does really help fuel economy and I can say that my mgp's are more consistent and staying above 20 more often.

Prinsu Design Studio Rack

 

[ntsqd]

Flat towing the avatar dune buggy behind my '66 Econoline van (like this):

yielded a consistent 1-2 MPG improvement. Given how un-aerodynamic the dune buggy was I find that particularly interesting. Especially since that 1-2 MPG was in the range of being a 10% improvement.

 

[bike4mee]

It's pretty easy to install a little 2x4 or 2x6 wind deflector attached to the camper. If I had more skills I would make a bowed deflector in the same manner. I must believe it saves a GPM Now to make one that can store my portable solar panel???