OT - Into the wind in both directions!

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[ Subject: OT - Into the wind in both directions! ]
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Ken Marcet writes:

I went for a quick little trip to the Post Office just to get some
stamps, and I was thinking this will be a nice easy relaxing ride.
Then I got out there and realized it was WINDY! so I made my way to
the PO and started back, and I was riding into the wind again!
Struggled to do 12 mph! What a workout!

There's more to wind than is readily apparent. Some of these effects
are shown in an analysis at:

http://www.sheldonbrown.com/brandt/wind.html

Jobst Brandt



Jobst Brandt

Ken Marcet writes:

I went for a quick little trip to the Post Office just to get some
stamps, and I was thinking this will be a nice easy relaxing ride.
Then I got out there and realized it was WINDY! so I made my way to
the PO and started back, and I was riding into the wind again!
Struggled to do 12 mph! What a workout!

There's more to wind than is readily apparent. Some of these effects
are shown in an analysis at:

http://www.sheldonbrown.com/brandt/wind.html

Jobst Brandt

Jobst wrote:

"Jobst Brandt


Jobst Brandt
"

Are you suffering from parkinson's?

Andres Muro writes:

Jobst wrote:

"Jobst Brandt


Jobst Brandt
"

Are you suffering from parkinson's?

I didn't write the above. You'll notice that the posting program
offered that trailer (and header) when I chose to cross post the item
from rec.bicycles.misc. So I deleted the item and reformatted it
although not all systems support deletions.

So what's your contribution to the subject of riding against or with
the wind? That is what this thread is about.

Jobst Brandt

Not much about riding against the wind except to say that unless I have
a strong tailwind I always feel like I am riding against the wind. The
intention in my previous post was merely to "go" against the wind.

Andres

wrote:

Andres Muro writes:


Jobst wrote:


"Jobst Brandt



Jobst Brandt
"


Are you suffering from parkinson's?


I didn't write the above. You'll notice that the posting program
offered that trailer (and header) when I chose to cross post the item
from rec.bicycles.misc. So I deleted the item and reformatted it
although not all systems support deletions.

So what's your contribution to the subject of riding against or with
the wind? That is what this thread is about.

Due to viscous drag, there is much less wind at altitudes of less than
1-meter/3-feet AGL. I barely notice winds that other cyclists complain
about.

--
Tom Sherman - Earth (Illinois)

Tom Sherman wrote:

Due to viscous drag, there is much less wind at altitudes of less
than
1-meter/3-feet AGL. I barely notice winds that other cyclists
complain
about.

Reducing center of drag from 4' to 2' gets about a 40% reduction in
wind with typical built-up terrain. In flat, open terrain, the effect
is much less. I'm not sure that there is that great a height difference
between typical recumbents and upright bikes either.

Peter Cole wrote:

Tom Sherman wrote:

Due to viscous drag, there is much less wind at altitudes of less

than

1-meter/3-feet AGL. I barely notice winds that other cyclists

complain

about.


Reducing center of drag from 4' to 2' gets about a 40% reduction in
wind with typical built-up terrain. In flat, open terrain, the effect
is much less. I'm not sure that there is that great a height difference
between typical recumbents and upright bikes either.

On a windy day, there is a huge difference between a recumbent with a
22-inch seat height and one with a 12-inch seat height.

Been there - done that.

--
Tom Sherman - Earth (Downstate Illinois, North of Forgottonia)

Tom Sherman writes:

Due to viscous drag, there is much less wind at altitudes of less
than 1-meter/3-feet AGL. I barely notice winds that other cyclists
complain about.

Reducing center of drag from 4' to 2' gets about a 40% reduction in
wind with typical built-up terrain. In flat, open terrain, the
effect is much less. I'm not sure that there is that great a height
difference between typical recumbents and upright bikes either.

On a windy day, there is a huge difference between a recumbent with
a 22-inch seat height and one with a 12-inch seat height.

Seat height is immaterial with respect to wind drag. It's the frontal
area that makes the difference. Pro racer Oscar Camenzind (CH)
descended bent over the bars with his head near the front tire while
his body was as high as ever, believing that, like and ostrich
(burying head in the sand), the wind could not see him if he got his
head low enough. Low seat hight is likewise not the measure of
effective cross section in the wind.

Recently being caught taking EPO, we don't see his style anymore.

Just the same, the concepts presented in the rider/wind analysis is
germane:

http://www.sheldonbrown.com/brandt/wind.html

The graphs clearly show how wind direction affects effort.

Jobst Brandt

wrote:
Tom Sherman writes:

Due to viscous drag, there is much less wind at altitudes of less
than 1-meter/3-feet AGL. I barely notice winds that other
cyclists
complain about.

Reducing center of drag from 4' to 2' gets about a 40% reduction
in
wind with typical built-up terrain. In flat, open terrain, the
effect is much less. I'm not sure that there is that great a
height
difference between typical recumbents and upright bikes either.

On a windy day, there is a huge difference between a recumbent with
a 22-inch seat height and one with a 12-inch seat height.

Seat height is immaterial with respect to wind drag.

[snip]

Jobst Brandt


Dear Jobst,

Here's a site that points out that the wind velocity typically drops
dramatically the closer you get to the ground:

http://www.onemetre.net/Download/Gradient/Gradient.htm

The graph suggests that wind speed drops quite noticeably from 1 meter
on down. Googling for "wind gradient" will produce numerous other links
about the same effect.

Carl Fogel