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Does this create downward pressure; is it a spoiler.

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  Does this create downward pressure; is it a spoiler. micky <NONONOmisc07@bigfoot.com> - 2017-07-06 19:39 -0400
    Re: Does this create downward pressure; is it a spoiler. jimp@specsol.spam.sux.com - 2017-07-06 23:56 +0000
      Re: Does this create downward pressure; is it a spoiler. benj <benj@nobody.net> - 2017-07-06 22:10 -0400
        Re: Does this create downward pressure; is it a spoiler. jimp@specsol.spam.sux.com - 2017-07-07 05:01 +0000
          Re: Does this create downward pressure; is it a spoiler. benj <nobody@gmail.com> - 2017-07-08 21:47 -0400
            Re: Does this create downward pressure; is it a spoiler. jimp@specsol.spam.sux.com - 2017-07-09 05:07 +0000
              Re: Does this create downward pressure; is it a spoiler. benj <benj@nobody.net> - 2017-07-10 18:08 -0400
                Re: Does this create downward pressure; is it a spoiler. jimp@specsol.spam.sux.com - 2017-07-10 22:23 +0000
        Re: Does this create downward pressure; is it a spoiler. micky <NONONOmisc07@bigfoot.com> - 2017-07-08 02:15 -0400
          Re: Does this create downward pressure; is it a spoiler. "F. Russell" <fr@random.info> - 2017-07-08 16:07 +0000
            Re: Does this create downward pressure; is it a spoiler. Sегg io <innvalid@invalid.com> - 2017-07-08 11:39 -0500
              Re: Does this create downward pressure; is it a spoiler. "F. Russell" <fr@random.info> - 2017-07-08 17:08 +0000
                Re: Does this create downward pressure; is it a spoiler. Sегg io <innvalid@invalid.com> - 2017-07-08 12:22 -0500
            Re: Does this create downward pressure; is it a spoiler. micky <NONONOmisc07@bigfoot.com> - 2017-07-10 23:41 -0400
    Re: Does this create downward pressure; is it a spoiler. "F. Russell" <fr@random.info> - 2017-07-08 16:17 +0000
    Re: Does this create downward pressure; is it a spoiler. "F. Russell" <fr@random.info> - 2017-07-08 16:36 +0000
    Re: Does this create downward pressure; is it a spoiler. Michael J. Strickland <michael06582@comcast.net> - 2017-07-09 18:07 -0400
      Re: Does this create downward pressure; is it a spoiler. pnalsing@gmail.com - 2017-07-09 15:36 -0700
      Re: Does this create downward pressure; is it a spoiler. micky <NONONOmisc07@bigfoot.com> - 2017-07-10 23:35 -0400

#639205 — Does this create downward pressure; is it a spoiler.

My car has what they call a spoiler on  the trunk lid, but it's attached
to the lid all the way across.  No air can flow underneath it. 

The top surface might be shaped right, but does the fact that no air can
go underneath mean it doens't really create downward pressure on the
rear end? 

If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
here, especially the 7,8,and 9th.
http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr

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#639207

micky <NONONOmisc07@bigfoot.com> wrote:
> My car has what they call a spoiler on  the trunk lid, but it's attached
> to the lid all the way across.  No air can flow underneath it. 
> 
> The top surface might be shaped right, but does the fact that no air can
> go underneath mean it doens't really create downward pressure on the
> rear end? 

Spoilers are not intended to create downward pressure on the rear end.

https://en.wikipedia.org/wiki/Spoiler_(car)

See the second paragraph.


-- 
Jim Pennino

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#639247

On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
> micky <NONONOmisc07@bigfoot.com> wrote:
>> My car has what they call a spoiler on  the trunk lid, but it's attached
>> to the lid all the way across.  No air can flow underneath it.
>>
>> The top surface might be shaped right, but does the fact that no air can
>> go underneath mean it doens't really create downward pressure on the
>> rear end?
> 
> Spoilers are not intended to create downward pressure on the rear end.
> 
> https://en.wikipedia.org/wiki/Spoiler_(car)
> 
> See the second paragraph.
> 
> 
Chimp, you are dumb as a box of anvils. You haven't a clue about science 
and yet continue to embarrass yourself and all Americans. You are worse 
than Trump.

Try learning some science rather than arguing stupid like Odd does. Yes, 
dumbass, SOME people put fake spoilers on their cars but that does not 
mean all spoilers are fake! Truth is spoilers DO create greater downward 
pressure on the rear end of a car. (Front is held down by wind and 
engine weight). Forget quoting that stupid censored irrefutable 
Wikileaker and learn some science. Wiki is written by dumbnuts like you.

Fact is that spoilers spoil the lift created by the fact that the car 
body is the shape of an airplane wing. This creates an upward force at 
high speed lifting the car. (old VW bugs are especially bad in this 
regard) The spoiler "spoils" the lift returning the forces on the car to 
normal weight which is an increase over the lifted weight.

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#639263

benj <benj@nobody.net> wrote:
> On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>> micky <NONONOmisc07@bigfoot.com> wrote:
>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>> to the lid all the way across.  No air can flow underneath it.
>>>
>>> The top surface might be shaped right, but does the fact that no air can
>>> go underneath mean it doens't really create downward pressure on the
>>> rear end?
>> 
>> Spoilers are not intended to create downward pressure on the rear end.
>> 
>> https://en.wikipedia.org/wiki/Spoiler_(car)
>> 
>> See the second paragraph.
>> 
>> 
> Chimp, you are dumb as a box of anvils.

The resident troll chimes in with the usual ad hominems and off topic
nonsense.

-- 
Jim Pennino

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#639526

On 07/07/2017 01:01 AM, jimp@specsol.spam.sux.com wrote:
> benj <benj@nobody.net> wrote:
>> On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>>> micky <NONONOmisc07@bigfoot.com> wrote:
>>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>>> to the lid all the way across.  No air can flow underneath it.
>>>>
>>>> The top surface might be shaped right, but does the fact that no air can
>>>> go underneath mean it doens't really create downward pressure on the
>>>> rear end?
>>>
>>> Spoilers are not intended to create downward pressure on the rear end.
>>>
>>> https://en.wikipedia.org/wiki/Spoiler_(car)
>>>
>>> See the second paragraph.
>>>
>>>
>> Chimp, you are dumb as a box of anvils.
>
> The resident troll chimes in with the usual ad hominems and off topic
> nonsense.
>
Notice CHimp is still dumb as a pet rock. Has no idea what spoiler is, 
how it works or why it's names as it is. So all he can manage to do is 
claim he's being abused by the truth and call others names. No science. 
No physics. No intelligent life of any kind.

Hey Bigfoot, a "spoiler" is not a wing. It dies not create lift in 
Either direction (up or down) It "spoils" the natural lift of the car 
which is shaped like a wing. Hence it creates "downward pressure" by 
removing the upward lift natural to a fast moving car.

Has anyone here seen a person (other than Bert and HVAC) as totally 
senile, ignorant, insane, kooky and arrogant as Jimp? He's a brother to 
Archie who just babbles on with random words and garbage and then when 
people explain the real science, he (and AP) just call them names to try 
to cover their senility and ignorance in a world-wide public forum.

Sorry, Chimp, but it's not working. You are still an embarrassment to 
the United STates of America (though not to Kalifornia) where your kind 
are the norm) even bigger than Trump.

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#639549

benj <nobody@gmail.com> wrote:
> On 07/07/2017 01:01 AM, jimp@specsol.spam.sux.com wrote:
>> benj <benj@nobody.net> wrote:
>>> On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>>>> micky <NONONOmisc07@bigfoot.com> wrote:
>>>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>>>> to the lid all the way across.  No air can flow underneath it.
>>>>>
>>>>> The top surface might be shaped right, but does the fact that no air can
>>>>> go underneath mean it doens't really create downward pressure on the
>>>>> rear end?
>>>>
>>>> Spoilers are not intended to create downward pressure on the rear end.
>>>>
>>>> https://en.wikipedia.org/wiki/Spoiler_(car)
>>>>
>>>> See the second paragraph.
>>>>
>>>>
>>> Chimp, you are dumb as a box of anvils.
>>
>> The resident troll chimes in with the usual ad hominems and off topic
>> nonsense.
>>
> Notice CHimp

The resident troll presents more ad hominems and pleads for attention.


-- 
Jim Pennino

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#639821

On 7/9/2017 1:07 AM, jimp@specsol.spam.sux.com wrote:
> benj <nobody@gmail.com> wrote:
>> On 07/07/2017 01:01 AM, jimp@specsol.spam.sux.com wrote:
>>> benj <benj@nobody.net> wrote:
>>>> On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>>>>> micky <NONONOmisc07@bigfoot.com> wrote:
>>>>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>>>>> to the lid all the way across.  No air can flow underneath it.
>>>>>>
>>>>>> The top surface might be shaped right, but does the fact that no air can
>>>>>> go underneath mean it doens't really create downward pressure on the
>>>>>> rear end?
>>>>>
>>>>> Spoilers are not intended to create downward pressure on the rear end.
>>>>>
>>>>> https://en.wikipedia.org/wiki/Spoiler_(car)
>>>>>
>>>>> See the second paragraph.
>>>>>
>>>>>
>>>> Chimp, you are dumb as a box of anvils.
>>>
>>> The resident troll chimes in with the usual ad hominems and off topic
>>> nonsense.
>>>
>> Notice CHimp
> 
> The resident troll presents more ad hominems and pleads for attention.
> 
> 
Chimp is just like a wind-up monkey, Set him down on the floor and he 
MUST jump around. Fun to watch.

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#639835

benj <benj@nobody.net> wrote:
> On 7/9/2017 1:07 AM, jimp@specsol.spam.sux.com wrote:
>> benj <nobody@gmail.com> wrote:
>>> On 07/07/2017 01:01 AM, jimp@specsol.spam.sux.com wrote:
>>>> benj <benj@nobody.net> wrote:
>>>>> On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>>>>>> micky <NONONOmisc07@bigfoot.com> wrote:
>>>>>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>>>>>> to the lid all the way across.  No air can flow underneath it.
>>>>>>>
>>>>>>> The top surface might be shaped right, but does the fact that no air can
>>>>>>> go underneath mean it doens't really create downward pressure on the
>>>>>>> rear end?
>>>>>>
>>>>>> Spoilers are not intended to create downward pressure on the rear end.
>>>>>>
>>>>>> https://en.wikipedia.org/wiki/Spoiler_(car)
>>>>>>
>>>>>> See the second paragraph.
>>>>>>
>>>>>>
>>>>> Chimp, you are dumb as a box of anvils.
>>>>
>>>> The resident troll chimes in with the usual ad hominems and off topic
>>>> nonsense.
>>>>
>>> Notice CHimp
>> 
>> The resident troll presents more ad hominems and pleads for attention.
>> 
>> 
> Chimp is just

The resident troll continues with the ad hominems and the pleading for
attention.

-- 
Jim Pennino

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#639403

In sci.physics, on Thu, 6 Jul 2017 22:10:03 -0400, benj
<benj@nobody.net> wrote:

>On 7/6/2017 7:56 PM, jimp@specsol.spam.sux.com wrote:
>> micky <NONONOmisc07@bigfoot.com> wrote:
>>> My car has what they call a spoiler on  the trunk lid, but it's attached
>>> to the lid all the way across.  No air can flow underneath it.
>>>
>>> The top surface might be shaped right, but does the fact that no air can
>>> go underneath mean it doens't really create downward pressure on the
>>> rear end?
>> 
>> Spoilers are not intended to create downward pressure on the rear end.
>> 
>> https://en.wikipedia.org/wiki/Spoiler_(car)
>> 
>> See the second paragraph.

Yes, it does say that, "The term "spoiler" is often mistakenly used
interchangeably with "wing". An automotive wing is a device whose
intended design is to generate downforce as air passes around it, not
simply disrupt existing airflow patterns.[1][2] As such, rather than
decreasing drag, automotive wings actually increase drag."

Thank you for pointing that out.  I really mean it. 

OTOH:
  I didn't bring up front spoilers but now I see in the same article it
says "Front spoilers, found beneath the bumper, are mainly used to
decrease the amount of air going underneath the vehicle to reduce the
drag coefficient and lift."  I don't get how decrasing the air going
underheant could reduce drag or lift, but if it decreases lift, that's
much like creating downward pressure, even if it's pulling down rather
than pushing down.  It seems to me. 

More relevant to my OP is found further down, "...a spoiler can still be
beneficial. This is because many vehicles have a fairly steep downward
angle going from the rear edge of the roof down to the trunk or tail of
the car which may cause air flow separation. The flow of air becomes
turbulent and a low-pressure zone is created, increasing drag and
instability (see Bernoulli effect). Adding a rear spoiler could be
considered to make the air "see" a longer, gentler slope from the roof
to the spoiler, which helps to delay flow separation and the higher
pressure in front of the spoiler can help reduce the lift on the car by
creating downforce. This may reduce drag in certain instances and will
generally increase high speed stability due to the reduced rear lift."

Undoing the Bernoulli effect, creating downforce, reduced rear lift:
These all refer to creating downward pressure, 

If we look at all the pictures of cars with rear spoilers on that
webpage, they are all, even the red one, separated from the trunk lid so
that air can flow underneath. 

There were two questions in my subject line: 
  Does this create downward pressure; is it a spoiler.

I don't want to quibble about whether it is a spoiler or not (although I
am still curious what people think), but I mostly want to know if the
one on my car and in the URL I gave creates downward pressure. : 

So my question remains, "...does the fact that no air can
go underneath mean it doesn't really create downward pressure on the
rear end? 

If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
here, especially the 7,8,and 9th.
http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr
"


>Chimp, you are dumb as a box of anvils. You haven't a clue about science 
>and yet continue to embarrass yourself and all Americans. You are worse 
>than Trump.
>
>Try learning some science rather than arguing stupid like Odd does. Yes, 
>dumbass, SOME people put fake spoilers on their cars but that does not 
>mean all spoilers are fake! Truth is spoilers DO create greater downward 
>pressure on the rear end of a car. (Front is held down by wind and 
>engine weight). Forget quoting that stupid censored irrefutable 
>Wikileaker and learn some science. Wiki is written by dumbnuts like you.
>
>Fact is that spoilers spoil the lift created by the fact that the car 
>body is the shape of an airplane wing. This creates an upward force at 
>high speed lifting the car. (old VW bugs are especially bad in this 
>regard) The spoiler "spoils" the lift returning the forces on the car to 
>normal weight which is an increase over the lifted weight.

So is one that's attached to the trunk lid for its full width capable of
creating a downward force?   

Even a little bit? 

It seems to me if anything it would make the car like two wings in
succession, and that it would increase lift,  Just a tiny bit, not
enough to make the car harder to drive, but still the opposite of a
spoiler. 

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#639430

On Sat, 08 Jul 2017 02:15:06 -0400, micky wrote:

> 
> I don't want to quibble about whether it is a spoiler or not (although I
> am still curious what people think), but I mostly want to know if the
> one on my car and in the URL I gave creates downward pressure. : 
> 

Aerodynamics is far too complex an issue to admit simple yes/no or
one-size-fits-all type answers.

Does a rear spoiler (not wing) cause a down pressure?  The answer
depends on many factors and it can be either "yes" or "no."

A more comprehensive discussion is found here:

https://www.carid.com/articles/will-adding-spoiler-make-my-car-more-aerodynamic.html

But a sad fact always remains: A lot of spoilers exist only for visual
effect and don't do anything at all (at least not intentionally).

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#639433

On 7/8/2017 11:07 AM, F. Russell wrote:
> On Sat, 08 Jul 2017 02:15:06 -0400, micky wrote:
> 
>>
>> I don't want to quibble about whether it is a spoiler or not (although I
>> am still curious what people think), but I mostly want to know if the
>> one on my car and in the URL I gave creates downward pressure. :
>>
> 
> Aerodynamics is far too complex an issue to admit simple yes/no or
> one-size-fits-all type answers.
> 
> Does a rear spoiler (not wing) cause a down pressure?  The answer
> depends on many factors and it can be either "yes" or "no."
> 
> A more comprehensive discussion is found here:
> 
> https://www.carid.com/articles/will-adding-spoiler-make-my-car-more-aerodynamic.html
> 
> But a sad fact always remains: A lot of spoilers exist only for visual
> effect and don't do anything at all (at least not intentionally).
> 

the only spoilers that 'work' are on drag racers, and dirt track racers. 
(lite cars)

on normal street cars, you can view the 'extra down force' created by a 
spoiler is really because of poor tires, not wide enough, not sticky 
enough.  The tires dont "hook up" as much as they could/should, 
therefore more down force is needed. But that force is quite small.


http://www.titantalk.com/forums/attachments/titan-general-discussion/114077d1293321841-titan-hood-scoop-pimped-red-car-huge-spoiler.original.jpg

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#639435

On Sat, 08 Jul 2017 11:39:31 -0500, Sегg io wrote:

> 
>  But that force is quite small.
> 

However, reduction in drag is always very important, but it is doubtful
that the common auto spoiler can have much effect in this area.

The trucking industry has been "streamlining" trucks because
the fuel savings can be quite significant.  Here is a link:

https://www.tc.gc.ca/eng/programs/environment-etv-menu-eng-2939.html

Railroad companies have also been experimenting with drag reduction
techniques.  Union Pacific, for example, has the "aero wedge:"

http://www.rrpicturearchives.net/showPicture.aspx?id=2526176

http://www.uprr.com/newsinfo/releases/environment/2013/0903_arrowedge.shtml


The only way to effectively reduce drag on automobiles would be
to introduce drastic changes in shape which most buyers would
reject.

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#639441

On 7/8/2017 12:08 PM, F. Russell wrote:
> On Sat, 08 Jul 2017 11:39:31 -0500, Sегg io wrote:
> 
>>
>>   But that force is quite small.
>>
> 
> However, reduction in drag is always very important, but it is doubtful
> that the common auto spoiler can have much effect in this area.
> 
> The trucking industry has been "streamlining" trucks because
> the fuel savings can be quite significant.  Here is a link:
> 
> https://www.tc.gc.ca/eng/programs/environment-etv-menu-eng-2939.html
> 
> Railroad companies have also been experimenting with drag reduction
> techniques.  Union Pacific, for example, has the "aero wedge:"
> 
> http://www.rrpicturearchives.net/showPicture.aspx?id=2526176
> 
> http://www.uprr.com/newsinfo/releases/environment/2013/0903_arrowedge.shtml
> 
> 
> The only way to effectively reduce drag on automobiles would be
> to introduce drastic changes in shape which most buyers would
> reject.
> 

totally agree, streamlining reduces gas consumption





but some sports cars have been streamlined for a while, they could 
improve too.  Some mags list the aero coeficient for the cars.

Mustang went from a brick in the 90s to more streamlined in the 2015

But then there is the SUV crowd...  And the 4 wheel Truck crowd

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#639894

In sci.physics, on 8 Jul 2017 16:07:27 GMT, "F. Russell"
<fr@random.info> wrote:

>On Sat, 08 Jul 2017 02:15:06 -0400, micky wrote:
>
>> 
>> I don't want to quibble about whether it is a spoiler or not (although I
>> am still curious what people think), but I mostly want to know if the
>> one on my car and in the URL I gave creates downward pressure. : 
>> 
>
>Aerodynamics is far too complex an issue to admit simple yes/no or
>one-size-fits-all type answers.
>
>Does a rear spoiler (not wing) cause a down pressure?  The answer
>depends on many factors and it can be either "yes" or "no."
>
>A more comprehensive discussion is found here:
>
>https://www.carid.com/articles/will-adding-spoiler-make-my-car-more-aerodynamic.html

Comprehensive is more than I neeed, but I did find near the end 3
pictures of cars something like mine, plus this tex, asterisks mine: 

"Rear Spoilers

Rear spoilers perform the same basic function as a wing, but for the
purposes of our discussion we'll clarify the difference between the two
since manufacturers often label them indiscriminately. A "spoiler"
mounts to the car's upper rear surface (trunk in most cases) and there
is **no gap** between the spoiler and the body. If there is a gap, the
aero piece would be considered a "wing". A spoiler's function and
effectiveness are dependent on its size, angle, and shape of the vehicle
it's mounted to.

If a spoiler's primary function is to provide down force, it will be
tilted at a more vertical angle. As such, high-velocity airflow coming
off the roof toward the back of the vehicle will be disrupted, reducing
its velocity and creating the high-pressure that results in downforce.
This downforce aids rear wheel grip, but it can also correct instances
where the shape of the vehicle is such that it tends to become unstable
at speed due to lift issues.

https://www.carid.com/articles/will-adding-spoiler-make-my-car-more-aerodynamic.html"

>
>But a sad fact always remains: A lot of spoilers exist only for visual
>effect and don't do anything at all (at least not intentionally).

Oh, I'm sure, but I see a big difference between one that barely works,
or even one that doesn't work at all, versus one which even if modified
has no possibility of working.  I'm glad that I haven't had the last
category. 

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#639431

On Thu, 06 Jul 2017 19:39:30 -0400, micky wrote:

> 
> If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
> here, especially the 7,8,and 9th.
> http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr
>

This particular spoiler, if it actually has an intended purpose other than
to add a "spicy" visual appeal, would be to (somewhat) reduce drag.

But with the top down on the convertible, the amount of drag reduction
would be negligible compared to the enormous drag produced by having
no roof.

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#639432

On Thu, 06 Jul 2017 19:39:30 -0400, micky wrote:

> 
> If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
> here, especially the 7,8,and 9th.
> http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr
>

More than likely this "spoiler" is for decorative purposes only.
It was just pasted on by the designer with no scientific purpose
in mind.

Today, the reason for spoilers is similar to the "tail fin" craze
of yesteryear:

https://en.wikipedia.org/wiki/Car_tailfin

It's a mystery to me why anyone would have wanted to be seen driving
a monstrosity like this:

https://assets.hemmings.com/blog/wp-content/uploads//2012/07/1959Cadillacfins_1500.jpg

We could, of course, argue that suck tail fins would impart greater horizontal
stability at very high speeds, but the only INTENDED purpose was for looks.

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#639651

On Thu, 06 Jul 2017 19:39:30 -0400, micky <NONONOmisc07@bigfoot.com>
wrote:

>My car has what they call a spoiler on  the trunk lid, but it's attached
>to the lid all the way across.  No air can flow underneath it. 
>
>The top surface might be shaped right, but does the fact that no air can
>go underneath mean it doens't really create downward pressure on the
>rear end? 
>
>If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
>here, especially the 7,8,and 9th.
>http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr

No the air only has to flow underneath if it relies on wing action and
has an inverted wing shaped cross section.

Air flowing over the back can still be deflected upward by a lip at
the rear edge. The upward deflected air provides a force (F = dp/dt)
which provides a downward force at the spoiler.

See you at the show trials - lol.
---------------------------------------------------
Michael J. Strickland			Reston, VA
---------------------------------------------------

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#639656

On Sunday, July 9, 2017 at 3:08:14 PM UTC-7, Michael Strickland wrote:
> On Thu, 06 Jul 2017 19:39:30 -0400, micky <NONONOmisc07@bigfoot.com>
> wrote:
> 
> >My car has what they call a spoiler on  the trunk lid, but it's attached
> >to the lid all the way across.  No air can flow underneath it. 
> >
> >The top surface might be shaped right, but does the fact that no air can
> >go underneath mean it doens't really create downward pressure on the
> >rear end? 
> >
> >If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
> >here, especially the 7,8,and 9th.
> >http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr
> 
> No the air only has to flow underneath if it relies on wing action and
> has an inverted wing shaped cross section.
> 
> Air flowing over the back can still be deflected upward by a lip at
> the rear edge. The upward deflected air provides a force (F = dp/dt)
> which provides a downward force at the spoiler.
> 
> See you at the show trials - lol.
> ---------------------------------------------------
> Michael J. Strickland			Reston, VA
> ---------------------------------------------------

Speaking of automotive downward forces...

http://bleacherreport.com/articles/1752888-can-a-formula-1-car-drive-upside-down

https://roadtrippers.com/stories/can-an-indycar-really-drive-upside-down-this-video-has-the-surprising-answer

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#639892

In sci.physics, on Sun, 09 Jul 2017 18:07:56 -0400, Michael J.
Strickland <michael06582@comcast.net> wrote:

>On Thu, 06 Jul 2017 19:39:30 -0400, micky <NONONOmisc07@bigfoot.com>
>wrote:
>
>>My car has what they call a spoiler on  the trunk lid, but it's attached
>>to the lid all the way across.  No air can flow underneath it. 
>>
>>The top surface might be shaped right, but does the fact that no air can
>>go underneath mean it doens't really create downward pressure on the
>>rear end? 
>>
>>If a picture will help, go to the 6th, 7th, 8th, 9th, and 10th picture
>>here, especially the 7,8,and 9th.
>>http://www.ebay.com/itm/2002-Toyota-Solara-SLE-Convertible-/322519401245?hash=item4b17a7831d:g:NqkAAOSwlMFZG8hm&vxp=mtr
>
>No the air only has to flow underneath if it relies on wing action and
>has an inverted wing shaped cross section.

Aha. 
>
>Air flowing over the back can still be deflected upward by a lip at
>the rear edge. The upward deflected air provides a force (F = dp/dt)
>which provides a downward force at the spoiler.

That's good.  That's exactly what I asked about.  Even more than I
asked.  Now I don't feel foolish about the last 6 years, when I had this
car.  I bought one w/o a spoiler two weeks ago. 

>See you at the show trials - lol.

Yeah, sure.  I'll be the one eating the popcorn. 

Seriously, I wasn't looking for a sports car or a race car, just one
whose top went down. They tacked a spoiler on anyhow. 

>---------------------------------------------------
>Michael J. Strickland			Reston, VA
>---------------------------------------------------

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