introduction forcings observations atmospheric turbulence ocean turbulence dimensional analysis

1. Introduction2. Forcings3. Observations4. Atmospheric Turbulence5. Ocean Turbulence6. Dimensional Analysis7. Basic Equations 8. Length Scales

Convective flows, Rayleigh-Nuselt numbers

Important parameters to consider in unstableflows Rayleigh Taylor Instab.

• The Atwood Number, A

• The width of the mixing zone,

• The non-dimensional time,

• The Fractal Dimension

21

21

²cgAt2

tH/Ag

/logNlog

D

N D

1

1

Boussinesq Aproximation consiss

On neglegting inertial accelerations on

density fluctuations, but allowing the

Gravitational accelerations.

Baroclinic Vorticity

Shocks in AIR of He and Kr Balls, Which is Which ?

0 500 1000 1500

0

5

10

15

20

25

ODCi

tir #260 tir #262 tir #265point 1 point 2 point 3 point 4

x [c

m]

t [µs]

x3x4

x2

x1 krypton M=1, 2

0 500 1000 1500 20000

100

200

300

UODC

i

= 370 m/s Uec

= 45 m/s

U [m

/s]

t [µs]

tir #296 tir #257 tir #254point 1 point 2 point 3 point 4

x4 x1x2x3hélium

M=1,05

0 5 100

1

2

M = 1,05 < 5% M = 1,2 < 5% M = 1,5 < 5% M = 1,7 < 5%

L aval/R

0

t/t0

a)b)c)d)

VelocityMagnitude

Volumeof Fluid

VorticityMagnitude

0÷10÷0,33 -106÷84

min

max

Basic Turbulence

Basic Turbulence

Basic Turbulence

Basic Turbulence

• Stratification causes strong vertical anisotropy!• Redondo(1990)