Aerodynamic streamlining (1936 General Motors)

[California98Civic]

Here is a video I found online that should be of interest. The use of aluminum powder to detect flow around the body types resting in water is interesting pre-animation visualization technology. The identification of “streamlined” features in the very boxy 1930s GM products really shows how far the industry and science has come. Though I bet if GM were still selling these shapes, they would be telling us how wonderfully streamlined they are.

http://www.youtube.com/watch?v=yQBqxIGaFeQ

[NeilBlanchard]

They are playing lip service to aerodynamics, that's for sure. The leap they make from hydrodynamics to the car is jarring.

[redneck]

They knew the shape of least resistance back then.
They still know.
It hasn't changed.
Yet they still refuse to build it.

Makes one wonder who they are trying to please ?
(hint- it's not about the people or the environment or preservation of resources)

>

[Frank Lee]

Watch the one with the homebuilt teardrop car and trailer!!! The Template came to life 80 years ago thanks to Angelo R. Noble!

http://www.youtube.com/watch?v=qdOxeZGRLiM

[cRiPpLe_rOoStEr]

Originally Posted by redneck

Makes one wonder who they are trying to please ?
(hint- it's not about the people or the environment or preservation of resources)

>

It was all about an obsession for science-fiction, no wonder many of those prototypes look like a spaceship.

Well, that car with a front-opening hatch quite resembles the Isetta from the 50s, which had that design feature quoted to resemble the cargo door of some nose-load cargo airplanes, altough it was often mocked as a "fridge door"

[kach22i]

Originally Posted by Frank Lee

Watch the one with the homebuilt teardrop car and trailer!!! The Template came to life 80 years ago thanks to Angelo R. Noble!

Excellent - I want.

There are some minor aerodynamic details on the 1936 model, but it's like easing the edges of a brick.
Automobile 2 - Odds And Ends Photos by kach22i | Photobucket


Would be a waste of time applying the full scale aerodynamic template to it, as it's a total fail.

[aerohead]

Originally Posted by kach22i

Excellent - I want.

There are some minor aerodynamic details on the 1936 model, but it's like easing the edges of a brick.
Automobile 2 - Odds And Ends Photos by kach22i | Photobucket


Would be a waste of time applying the full scale aerodynamic template to it, as it's a total fail.

If you inspect Hoerner's 'AERODYNAMIC DRAG',his treatment of canopies and blisters(pontoon fenders and separate greenhouse) actually goes in the other direction.
Instead of a 5:1 fineness ratio,he'll recommend 10:1.
It has to do with interference drag and super-velocities created by these individual elements when placed in proximity to one another.
This is a reason for keeping the aerodynamic 'singularity' of the 'Template' half-body rather than 'combination-forms.'
Since the half-body doesn't allow separation and produces minimum shear it's virtually unbeatable for a door-slammer.
PS,the beauty of the 1936 Chevrolet shown is that it is a body-on -frame construction.One can unbolt it and discard it,replacing it with a Jaray or K-Form body, cutting it's drag in half.More with the pumpkin seed.

[kach22i]

Originally Posted by aerohead

If you inspect Hoerner's 'AERODYNAMIC DRAG',his treatment of canopies and blisters(pontoon fenders and separate greenhouse) actually goes in the other direction.
Instead of a 5:1 fineness ratio,he'll recommend 10:1.

One of these days I'm going to have to read the list of books recommeneded in this forum. You are a treasure trove of information Aerohead.

Let's see if I have this right, things I've learned this week...........

3:1 ....................free air teardrop ratio.

5:1 ...........fineness ratio of a body in proximity to a ground plane.

10:1.....canopies, blisters, pontoon fenders and separate greenhouse.

Originally Posted by aerohead

It has to do with interference drag and super-velocities created by these individual elements when placed in proximity to one another.

I am also interested in the purposeful introduction of "air curtains" over wheel wells and "roof wing slots" which increase air velocities (and lower pressure) to manage/influence the flow of slower moving (high pressure) air masses.

The simple model of the 3D template is wonderful, but quickly dissolves against the brutalities of adaption to existing car/truck bodies.

We need a bigger bag of tricks in my opinion to post-treat our road bricks.

[freebeard]

Now why did I know Neil Blanchard would like that?

Originally Posted by kach22i

The simple model of the 3D template is wonderful, but quickly dissolves against the brutalities of adaption to existing car/truck bodies.

We need a bigger bag of tricks

For all the concern people have for the profile of The Template, nobody ever turns it and looks at the semicircular 'Procrutean Bed' profile that it presents on that axis.

[Sven7]

Originally Posted by redneck

They knew the shape of least resistance back then.
They still know.
It hasn't changed.
Yet they still refuse to build it.

Makes one wonder who they are trying to please ?
(hint- it's not about the people or the environment or preservation of resources)

>

It's easier to sell a fancy new 30mpg car than an ugly 100mpg vehicle. They're not the Park Service; it's a business. Don't get me wrong; I'd love to see more VW XL1's around, but they're very expensive to produce.