Aerodynamics Matter !!
Hello All. First post here... wanted to share some data on aerodynamics. I am designing an ultralight (under 100 lbs/ft) small travel trailer and wanted to find out the effect of shape on aerodyna...
Forum Discussion
93Cobra2771 wrote:Cup fan wrote:
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Something I would be curious to know would be how the attitude of the trailer behind the TV affects mileage. I see a lot of trailers going down the interstate that aren't level. The nose
of the trailer is often much lower than the rear, perhaps due to improper hitch ball height, or improper springbar adjustment. I know for me, proper hitch set-up is huge as far as handling is concerned.
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Nose up or nose down also affects mpg, as you are now exposing either more roof area (towing nose down) or more bottom area (towing nose up) to the air when towing. If perfectly level, you only have the nose and whatever objects are above the roofline.
On the flip side of that, being slightly nose down gives more stability while towing.
I was curious also so I ran a simulation with the nose up and nose down by 2 degrees on the trailer only. Results compared to the same box trailer were as follows...
Nose Down - 1.5% decrease in force required (Interesting to note that the down force doubled)
Nose Up - 10.9% decrease in force required
Conclusion: Nose down doesn't make a difference but nose up is actually better. You will see that in the images posted later. Hmmm. Not what I expected.
Apparently I am barely smart enough to figure out how to use the CFD software but not quite enough to figure out how to post a picture of it here!
Ron
