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kiticat · January 10th 06, 06:28 PM posted to uk.sci.weather

wrote:
Hello,

How do I calculate tornado's kinetic energy, if known

1) velocity inside tornado
2) heght
3) radius

I calculed it in following manner:

K=1/2(Iw^2)

w=V*R

I(cylinder, z)=1/2(MR^2), M=ro*Pi*R^2*h

K=1/4(ro*Pi*R^2*h)(V*R)^2

But sort of "not realy sure" that I can use rigid mechanics formulas in
case of air ...

Thanks in adwance for your reply.

This is what my dh had to say on the matter (he works in aerodynamics
but not in this field).....

If I remember correctly, there are two forms of stable vortex. The first has
V proportional to R (solid body rotation). The second has V proportional to
1/R. My impression is that a tornado is essentially the latter with a small
tube of dead air around the core (otherwise the speed goes infinite). The
basic approach to the calculation of kinetic energy looks about right,
except for the assumption of solid body rotation (constant w).
--
Sarah
*******************************************
Give Mr. Snipa's wife's knife a swipe.