Waynes Rule

Below is a pre-amble to a new yahoo group I have started to discuss thermals. I would ask all interested gliding pilots to join in and learn, or teach.

http://groups.yahoo.com/group/thermal_truth/

Ok, we know the shapes, triggers, the sizes, the volumes, the heights, the strengths, the distances between thermals.
We speculate on rotation, blue holes, convergiences, moisture content, adiabatic lapse rates, height to spacing ratio's and a dozen other thing relating to thermals.
We have had countless thermal studies, used blipmaps, radars, sensors and test flights for nearly a hundred years.
But we base it all on the blind understanding that a thermal rises simply because it is hotter than the air around it, or, at best, less dense that the air around it.
This is not true.
We feel a wind gust on the airfield in the morning and we know the day has "started". Sure enough, a willy-willy or dust-devil appears, usually triggered by the activity on the grid, swirling off down-wind between the pie-cart and the tug/glider combination, or perhaps the winch and the glider.
We know a thermal bubble has just broken loose, the willy-willy is the under-current eddieing around below it in suction, the breeze filling the void that the thermal left behind.
This is not true.

We see a bubble in the water beside us as we rise in our scuba gear. The bubble has eddies below it, turbulence beside and below it. It has a smooth, rounded top and a flat bottom. This is true, however,it is not rising by itself, as all seem to think, it is being displaced by the water.
Thermals are no different or they would break Waynes Rule.

After years of racking my brain on this subject -my passion- and debating it with freinds, scientests, sceptics and expert alike, I cannot seem to make people understand what I see as the truth.

Perhaps I am mistaken, I welcome education from my peers in the gliding community. If I am not, many people in the world will benefit from this understanding, as the rules will probably apply to heating of just about everthing.

I am taking liberty calling the theory Waynes Rule, I apologise to the purists and the great scientists of the past whose work with gravity and mass I am borrowing the theory from, but for the discussion, its

Waynes Rule.

Wayne Carter
(bagger)

Wayne,

It's not clear to me exactly what your "rule" is from the above
paragraphs. Could you please restate your hypothesis more
succinctly?

I can't tell if you are a crank or just a nit-picker.

What practical difference is there between:

Standard statement:
"The air in a thermal rises because it is hotter and less dense than
the air around it."

Your rule:
"The air in a thermal rises because it is displaced by the denser,
cooler air around it."


Todd Smith

toad wrote:
I can't tell if you are a crank or just a nit-picker.

What practical difference is there between:

Standard statement:
"The air in a thermal rises because it is hotter and less dense than
the air around it."

Your rule:
"The air in a thermal rises because it is displaced by the denser,
cooler air around it."

Absent gravity, of course neither statement is accurate. Include gravity
and the second statement is perhaps more conceptually useful though still
begs the question. All air gets pulled downward, but less dense air is
forced to rise because it is "squeezed" upward by the more dense air around
it. I think that is perhaps conceptually even more "accurate".

On May 1, 2:50 pm, Jim Logajan wrote:
toad wrote:
I can't tell if you are a crank or just a nit-picker.

What practical difference is there between:

Standard statement:
"The air in a thermal rises because it is hotter and less dense than
the air around it."

Your rule:
"The air in a thermal rises because it is displaced by the denser,
cooler air around it."

Absent gravity, of course neither statement is accurate. Include gravity
and the second statement is perhaps more conceptually useful though still
begs the question. All air gets pulled downward, but less dense air is
forced to rise because it is "squeezed" upward by the more dense air around
it. I think that is perhaps conceptually even more "accurate".

I had pretty much assumed that we were including gravity :-)

Todd

Wayne:

When my friend Burner fills his passenger balloon with hot air and
looses the tether, it rises because the air inside it is less dense
than the air outside it.

Tuno's Rule: A thermal is a hot air balloon without the balloon.

2NO

I forgot to add -- Tuno's Rule assumes there are no conveyer belts
near the balloon.

It's call "buoyancy". This is not a new concept.

On May 1, 3:38 pm, Tuno wrote:
I forgot to add -- Tuno's Rule assumes there are no conveyer belts
near the balloon.

Is my calender right ? It is May 1st, not April ? Right ?

Todd Smith

Matt, go to the yahoo site for more information.
Toad, there is no practical difference, ther result is the same, there is however, considerable mis-understanding on the cause
Jim, top of the class today
Tuno, wrong, sorry. The balloon rises because it is displaced by the denser air around it.
The fact that it is hotter, lighter, smaller, larger or a different color does not influence its rising without the consideration of the denser air around it.
Bouyancy is not new, you are correct there

http://groups.yahoo.com/group/thermal_truth/

bagger