Aerodynamic Streamlining Template: Part-C

[aerohead]

Originally Posted by RobertSmalls

Phil, that looks great. In your mind, what kind of front wheel skirts are those?

Another random thought: how much suspension deflection should be assumed when working out your approach and departure angles?

Perhaps a moderator could copy the new, prettier, "accurized" image to the first page of this thread?

Robert,the skirts could be like basjoos has done with AEROCIVIC or the pantograph type I've been threatening to do.'could also be like Ford Probe-IV with inner fender and elastic spat.
With respect to deflection,I believe that if the car is ballasted to SAE test weight ( adding 300-pounds ) and the approach,ramp,and break-over angles are respected,then no ground strike should occur.************** I will re-visit my SAE Handbook to make sure they're not talking about full gross weight.That's worth checking and I should have already done that.Sorry!

[aerohead]

Originally Posted by 3-Wheeler

Hi Phil,

I responded to this portion of your post separately since it merits emphasis....

I have pondered doing more with the underside of the Honda Insight Tail Extension to get the active angle closer to 6 degrees or so all the way back to the lights.

One big concern I have is the health of the old country roads I travel on during commutes to work. Suffice it to say they are BUMPY.

If I had a portion of the tail that simply dropped down lower than the current *hard slope*, that moveable portion would make one heck of a racket back there with all the bumps in the road.

It seems that the dropped portion would need some sort of damping, maybe in the form of soft foam rubber, or something else to cushion that constant vibration from the rough road surface.

It would be nice if the soft foam were sealed to prevent picking up moisture from the snow (or rain) when driving down the road.

Beyond that I can see using a small diameter rubber wheel to raise the moveable portion when clearing driveway aprons and such.

Jim.

Jim,sorry to hear about the ice hicky.I tore one of my wipers attempting to free it from the icy windshield.
I hear ya with respect to wash-boarded roads and such.
My thoughts have gravitated towards a simple lever/cable/pulley system to start out with,and probably only for paved highway and interstate use.
In a situation like yours,you may already have to moderate your speed due to the road conditions,and the diffuser/fairings/strakes might want to just remain stowed until you can really 'let 'em out.'
I like the idea of damping.I'd also like to do something so light,that something like the auto-focus ranging system of a camera could be co-opted to trigger a solenoid if it 'saw' an approaching hazard,lifting the belly instantaneously until danger passed.
Your idea about wheels has been swimming around in my head with respect to wheel fairings which lay just above ground level.The lead fairing would lift over an obstruction on its wheel and a linkage connecting it to the trailing fairing would raise it also so it wouldn't be creamed either.And these would have viscous cuing as in shock absorber or audio turntable arm so they couldn't lower before danger passed.
Wheels projecting from the underside of the diffuser etc. could be 'all terrain following,' in a low tech fashion.Simple,low-cost,easy maintenance,replacement.

As I read more and more posts from members in 'winter' climes,it seems like there will be many challenges for active devices where 4-seasons are involved.Snow and ice really is a challenge.No doubt some us will be getting into this and I'm sure issues will rear their beautiful little heads!

[COcyclist]

I would love to see someone with Photoshop skills overlay the NEW template over this photo of the VW XL1. Botsapper? Neil?

Volkswagen Reportedly Preparing 79 MPG Up Minicar With XL1 Powertrain - Rumor Central

[KamperBob]

Here's the side view image.

[BamZipPow]

Originally Posted by COcyclist

I would love to see someone with Photoshop skills overlay the NEW template over this photo of the VW XL1. Botsapper? Neil?

Using Picasa to straighten/crop the piccies, OpenOffice Draw to trace some colored lines, Picasa to git a screen cap, and then Merge to overlay them...

[KamperBob]

Nice, BZP! (It's cool how VW logos look right with the image flipped too.)

[COcyclist]

You guys rock!

Originally Posted by KamperBob

Even the side skirts/spats/wheel boattails on the VW remind me of Phil's latest rendering. Thank you!

[BamZipPow]

Colored the lines of the template bottom and applied it on top of my T-100...


Using Picasa and Merge (75% bias on the merge) it would appear that my side skirts are matching up pretty well...

I'm thinking about adding some tapers between the wheels but still hidden by the side skirts now. I'll probably try some pool noodles (cheap, easy to work with, and resilient) as my initial test material.

I wonder how well pool noodles will work on the front A arms as well...

Again...if anyone wants the OpenOffice Draw file that I traced over the template with...let me know.

[aerohead]

Originally Posted by RobertSmalls

Phil, that looks great. In your mind, what kind of front wheel skirts are those?

Another random thought: how much suspension deflection should be assumed when working out your approach and departure angles?

Perhaps a moderator could copy the new, prettier, "accurized" image to the first page of this thread?

I grabbed the Handbook.All the angles are based on Gross Vehicle Weight,not the 300-pound SAE test weight protocol.

[RobertSmalls]

Originally Posted by aerohead

I grabbed the Handbook.All the angles are based on Gross Vehicle Weight,not the 300-pound SAE test weight protocol.

Incidentally, the two values are pretty similar for the Insight. GVWR makes sense. For designs for my own use, I'll use the greatest load I expect to see, whether that's above the GVWR or not.

BZP, that's an interesting way to use the bottom of the template. Just make sure that people don't align the template like that and think they can draw inferences about the top of the car.

We should attach instructions to the template, because it's not intuitive how it should be used.