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Непрочитано 28.05.2013, 11:49
#121
Ромашка
Windsurfer

 
Sail Number: 4444
Club: клуб всемирного глиссирования
Location: Астрахань
Weight: 97 kg.
Благодарностей: 46
Ветер не везде "одинаковый"
http://www.blur.se/2009/02/09/wind-s...ct-or-fiction/

More About Pressure Gradient And The Coriolis Effects – The Technical Background
Wind is caused chiefly by differences in air pressure. Regional differences in air pressure are equalized from the lowest height, moving upwards, and this means that high-pressure air sinks to replace rising low-pressure air from low to high. The air temperature also has an impact on air pressure; rising (warm) air rotates anticlockwise, while sinking (cold) air rotates clockwise. This process is described by the following equations, where;

P = CρT (pressure exerted by the gas)
C = Constant
ρ = density of the gas = mass/volume
T = Temperature of the gas
PGF = Pressure Gradient Force

Forces that act on the air masses are as follows:

1. Pressure Gradient Force
PGF = ΔP / (ρ * d)

ρ – density of the air
ΔP – is the change in pressure
d – is the distance

2. Coriolis Force

CF = 2 * Ω * Vg * sin Φ

Ω – is the rotation rate of the earth
Vg – is the geostrophic* velocity
Φ – is the latitude that you are at

3. Centripetal Force (Of The Rotating Wind, Not The Earth)

CPF = m * v² / r

m – mass
v – velocity
r – radius


http://www.blur.se/2009/02/09/wind-s...ct-or-fiction/
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