Vortex strake device; reducing aerodynamic drag

[mallrat]

"It depends" on your driving routine. Lots of stop-and-go driving, or otherwise under 35 mph? Aerodynamics aren't going to help you much. Long stretches at sustained speeds over 45mph? More likely to see a return, especially on boxy vehicles and OTR tractor trailers as shown in some of the early posts. On the commercial vehicle side, a full boattail or "Trailer Tails" may show greater returns, but they also have other drawbacks like somewhat complicated loading/unloading, extra weight, and more likely to be damaged in the truckstop parking area. Standard fenders and bumpers have a hard enough time surviving

[Otto]

Another cheap trick to make VGs is to use clear plastic corner protectors for drywall, as sold at Home Depot. It's a clear plastic strip with an L shape cross-section with sides ~3/4" high, comes in maybe 8' lengths, to protect outer corners of sheetrock wall surfaces in high traffic places like your kitchen. Hardly costs anything, and you could make dozens of VGs out of just one strip.

Being clear, if you can find a good and durable clear two-sided tape, you could stick these onto your car and still see the paint underneath, a sorta stealth application not too noticeable. Or, apply with glue gun? Clear Shoe Goo? Or, whatever works durably in weather, but is removable later without damaging the paint.

I suspect a Coroplast undertray might be a great place to experiment, if you had a GoPro camera to record the tuft tests, and a secure mount for the camera.

[radioranger]

I agree , if I start seeing them on the highway I'd take note, this is almost 10 yr;s old no ,

[mallrat]

Originally Posted by radioranger

I agree , if I start seeing them on the highway I'd take note, this is almost 10 yr;s old no ,

Got any big truckstops in your area? Some of the mega-fleets are running "skirts" underneath the trailer as well as "trailer tails" that fold against the rear doors for loading and unloading. You can occasionally see Airtabs along the rear edge of the trailer as well as the rear fairing on the sleeper or cab of the truck. I personally haven't seen any of these "strakes" in operation, but I got away from being a truckstop mechanic a couple years ago.

[gone-ot]

FE is a "box" funtion, ie: length x width, where length is TIME and width is the amount of SAVINGS.

Thus, a long TIME x small SAVINGS can still be beneficial, provided the TIME element is sufficient.

[Otto]

Originally Posted by radioranger

I agree , if I start seeing them on the highway I'd take note, this is almost 10 yr;s old no ,

I would not buy into that reasoning, at all: If the trucking industry had any clue, they'd all be driving rigs like the aero bigrig on this website, which gets about twice the fuel mileage as the much-bragged about latest from Mack, Kenworth, etc.

Either the trucking companies have not spent 10 minutes perusing Hoerner, NASA, or Hucho, or they cannot be bothered.

The r&d facility for a major trucking manufacturer is about 4 miles from my house. They have an open house weekend every so often, which I've attended. I know for a fact that they have Hucho in their library, as I borrowed it via interlibrary loan. Do their products show much, if any, aero improvement as is common knowledge from the above-mentioned sources? Not really. These people are willfully ignorant, or just blow it off, or maybe they mess with pissants while being trampled by elephants.

Sorry about the rant. But, basic vehicular aero optimization has been known and published for about 80 years now, and not many with the power to make changes act accordingly. It's pathetic.

[mallrat]

Also a lot of stuff out there that truly deserves to be labeled "snake oil", many drivers and trucking company executives just lump everything in there and figure if the OEMs don't put it on or the EPA doesn't require it, it must be bunk. The Owner/Operators that are trying to save fuel and money have a lot of information to wade through, much of it false.

I think the consumer figures "if it worked, the manufacturer would install it" and the manufacturer figures "if the consumer wants it, they would demand it or install it themselves."