More semi aeromods

[aerohead]

Originally Posted by redneck

I talked with a representative of Smart Truck today. I asked him the purpose of part C. He explained to me that part C was a rear diffusser and that the whole Under Tray System was designed to compress and tunnel the air. Thus speeding it up before entering the low pressure area. If you look closely at the bottom of part C you will notice a slight downward angle that helps with final compression.

I told him about this website so maybe he will chime in later.



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He probably should not use the 'compress' and compression' as terms to describe what his product does.This phenomena would not begin to occur until around 250 mph.
Better that he should say it 'accelerates' the flow which actually lowers its pressure.
It's hard to imagine that it does anything other than ride in the wake of the first component ahead of the wheels and the wheels themselves.

[Joenavy85]

Originally Posted by aerohead

He probably should not use the 'compress' and compression' as terms to describe what his product does.This phenomena would not begin to occur until around 250 mph.
Better that he should say it 'accelerates' the flow which actually lowers its pressure.
It's hard to imagine that it does anything other than ride in the wake of the first component ahead of the wheels and the wheels themselves.

He should have just said the Venturi Effect

[redneck]

Originally Posted by aerohead

He probably should not use the 'compress' and compression' as terms to describe what his product does.This phenomena would not begin to occur until around 250 mph.
Better that he should say it 'accelerates' the flow which actually lowers its pressure.
It's hard to imagine that it does anything other than ride in the wake of the first component ahead of the wheels and the wheels themselves.

I may have interpreted what he said and came up with the word compress on my own.

The trailer pictured has sliding tandems. They are normally slid foward for city driving (less turning radius) and slid back for highway use or anywhere in between to get the correct maximum weight per axle allowed by law.

When the tandem is slid back for highway use, the reason for having part C in the system then becomes more apparent. IMHO.

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[aerohead]

Originally Posted by Joenavy85

He should have just said the Venturi Effect

I see where you're going,but I believe that without an 'enclosed system' which a venturi is dependent upon,there is nothing present( as the wall of a carburetor) in the local flow environment to 'force' the acceleration around or under.

[Vekke]

Originally Posted by aerohead

That's the $Trillion idea! If you're first to the Patent Office and you can obtain venture capital for commercial production you'll amass a fortune that would make Xerxes blush.

I dont know if same patent laws apply to states, but in europe if you say your idea that clear in some forum you cannot apply anymore patents to that idea...

There are trailers already in europe which look like boattails, so it would be very hard to get patent for something which you just do more longer boattail.

[aerohead]

Originally Posted by Vekke

I dont know if same patent laws apply to states, but in europe if you say your idea that clear in some forum you cannot apply anymore patents to that idea...

There are trailers already in europe which look like boattails, so it would be very hard to get patent for something which you just do more longer boattail.

Vekke,if you come across any photos of these trailers it would be great for you to post them.
Once a person can 'see' that something has actually been done,it somehow validates the concept,and all of a sudden it's worthy of application.

[Vekke]

No personal photos, but is this enough for starters?

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not so curvy kammback trailers is on finnish roads. I dont know if someone has modified his own trailer or do some trailer company build that kind of models :/. I will try to remember take some pictures next time I see one.

[Piwoslaw]

DHL teardrop trailer - Google Image Search

[Joenavy85]

Originally Posted by aerohead

I see where you're going,but I believe that without an 'enclosed system' which a venturi is dependent upon,there is nothing present( as the wall of a carburetor) in the local flow environment to 'force' the acceleration around or under.

i should have stated that as a general description, not a literal term(for example, standing between 2 building will cause you to experience an increased wind velocity but technically isn't a venturi since it's not enclosed). reduce the area for the fluid to flow through and you will increase it's velocity, and reduce it's pressure, likely that piece on the back wouldn't do very much of that since it's no in contact with the ground and therefore doesn't fully enclose the air path underneath, but it is close

[kach22i]

Another whole truck aero-design.

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