Class 8 Truck modifications

[craysus]

Obviously I am not a master at using photoshop etc...but the concept on the aero is shown here..A few things would be improved in production over the picture (Due to my photoshop skills!)..EG the wheel fender on the hood is too high increasing drag..and not blended to the hood line correctly..
I would be using the front bumper inlets with some ducting for airflow for normal trucks, but would probably need to utilise a "snorkel" up beside the window for our outback trucks..(Cleaner air).
I also couldnt figure out how to remove the sunvisor and reduce the height of the running lights (Conversion to LEDs)..

[freebeard]

I think we can get the picture.

I think the fender contour is fine, the air will follow the compound curve and it's all within the frontal area anyways. I'd look at the transition from the wheelwell to the steps and tanks.

The sun visor is also within the frontal area, but there looks like some opportunity between the doors and moon-roof/sleeper cab windows to suppress vortexes there.

Also radius the front edge of the side skirt so it underlaps the tractor's fender skirts.

All IMHO, of course.

[craysus]

Potentially a compound radius deflector on the transition between the cab doors and the leading edge of the sleeper? To help maintain laminar air attachment?

The transition between the fender and the top of the tanks / top step area is a definate concern..I think reflowing the fender such that it is more similar to the aero bullet truck design might be required.. (Effectively flattening the top by 2-3", and tear dropping it backwards onto the step in a more shallow curve)


Another thing I am contemplating is the effectiveness of putting a V chin spoiler under the front of the truck...from the centreline of the bumper underside..to just infront of the wheels..to reduce airflow under the truck..Obviously most things would not work in this area due to getting hit / damaged, however how would a 6" high BRUSH work in this area? like the below product
https://www.industrialbrushware.com....s.php?catid=46
worthwhile? or unicorn corral ?

[craysus]

MK 2...

image hosting free

Copied a Kenworth T680 sleeper cab onto roof...large compound radius, and helped also remove the sun visor easily from the picture

Added some side deflectors between cab and sleeper .

Lowered fender height by around 3"

Defined (Would need smoothing) the drivers step / side skirt width change section slightly...this would need flowing and rounding out at rear edge, and a transition from the fender directly onto it..

More suggestions the merrier..

I am in liaisons with a thermal airflow expert for the engine cooling, a radiator specialist, have a staff member onhand who can make ANYTHING in fibreglass / etc (has made entire WW2 plane replicas).
I will be also looking for government funding for green purposes on the R&D side of this..the first 1-2 prototype conversions may end up costing VERY little..

[gumby79]

On the brushes would be purity Kangaroo proof.
Call in an order that is 3 bristles thick in a 45-60°angle. Each row counter the next.this will give some stability and stiffness. Im gussing with there 250mm (~9") bristles. they would be your desired 6" length . maby do 5 of eachV and U .

For V
Dump the air into the front brakes/wheel wells. ( a low pressure zone). Best would be to make the end an air curtain th direct the air around the front wheel. Fill the finder tire gap with the brushes on the front 2/3.


U shape
The chin would be back behind the bumper on a gental curve out to the tyer ~ 1/3 in from the outer edge With out air curtains. With them iirc it would lind up with the out side of the tire creating a low presure high velocity on the front of the tire.

. Park a truck pointed into the wind take notice of the bow wake . Try to mimic this natural shape, as nature is pointing the parh of least reassurance.
Like kach22i did hear.
http://ecomodder.com/forum/532983-post596.html

Thoughts I had what is goung to keep a kangaroo from sliding up the hood and coming through the windshield. A brush/ kangaroo garde made with airfoil shaped tubing. Adjust the angle of attack in loacal air( the loacal direction of air traval accounting for the bow wake . Not the direction of road travel. ) to move and accelerate the air in the direction most suitable for your shape. If dond right the Airfoils direction of lift will be forward. (Resulting in a negative drag coefficient?)

http://ecomodder.com/forum/showthrea...mk3-34517.html

Maby run both stiles U in frontto air curtains at 3"deep and V at 6"deep continued filling of the turbulent low presure wheel well. Even add a secondary air curtains from the V at the back of the tyer.

[freebeard]

http://ecomodder.com/forum/showthrea...ics-17717.html Your mirrors are it the problematic flow around the A-pillar. Modern buses and fire engines cantilever them forward. (Or pull them back like on the driver's side in the example) The drivers don't seem to mind.

I'd like to see a hood contour that has a bluff contour like the sleeper cab. But I recognize the value of the sightline. The driver can tell if there is a wheelchair snagged on the front bumper. Wheelchair user taken on 50-mph ride - US news - Life | NBC News

The brush guards are longitudinal to the air flow, across the flow they would just bend back unless they were backed by an inflated tube or something. Here's an example of a diverter that shows the strength required:

[seifrob]

Did anybody mention tractor-trailer gap management already?
You want half- cone or rounded edges on front side of your trailer, unless you are filling the gaps with stretched spandex. This prevents vortex generation in the gap.
Somewhere else on the forum it was already discussed, halves of large diameter sewage pipes should suffice iirc.


EDIT: I found the thread: http://ecomodder.com/forum/showthrea...tml#post502508, http://ecomodder.com/forum/showthrea...ent-33247.html


original image posted by aerohead

[freebeard]

Did anybody mention tractor-trailer gap management already?

Permalink #12

Fairings and Vortex traps called out in the illustration.

[seifrob]

thanks, its hard to keep track on my 3.5" phone (never mind writing answers).

[freebeard]

To be fair, it was buried in an infographic.

I spent some time trying to find an academic PDF that compared solutions for the tractor-trailer gap; maybe someone else can point to it. I did find this post I made in a relevant thread: http://ecomodder.com/forum/showthread.php/canard-bluff-bodied-box-33231.html. The post discusses perforated flaps and visors.