In this article, I am speaking about fluid dynamics, hydrostatic
pression, Bernoulli law and similar uninteresting things - a warning
to prevent people to complain - if not interested, skip it right now;-)

>From the very beginning, I have to ask myself about the usefullness of
continuing this senseless debate over Bernoulli and water sinking.
However, I believe when the nonsense gets into such enormous proportions
and is about to be used for pseudoscientific argumentation, it's good to
bring a correction, even if debating with someone who is not trained in
physics is not challenging.

I am affraid that there is not too much to discuss in these recent
longish postings with rice field pictures, nothing that would withstand
a serious analysis. Thus I chose not to address every long paragraph
separately, just aggregated answer to address all together.

Bernoulli law is of course valid in every dynamic system with fluids,
and of course the example with the airplane profile is right: where the
speed is higher, the pression is lower. The same in the Danube case. My
point is that these phenomenons can be safely neglected in Gabcikovo case
because of low speed of the stream, unless wanting to go through a
calculus with many digits just for fun. High precision calculus with
GIGO data is senseless. (in math jargon GIGO is for garbage in, garbage
out - low precision data cannot give good answers)

Of laminar or turbulent flow. To assess this, a huge amount of exact
data of profile of the bottom would be required, and imagine the pain
of collecting such data. Laminar regime becomes turbulent for sure if
a parameter called Reynolds number grows beyond a certain limit value.
Under some much lower value, it will be laminar for sure. Between the
two, it can be either laminar or turbulent depending on boundary
conditions (shape of the bottom) and it's the chaos theory that gives
instruments to assess the phenomenon in a determinist way. However,
equations are highly non-linear and require a detailed knowledge about
the boundary conditions, in this case the bottom of the riverbed. This
exercice has no utility in Danube case. Some of us already saw a river
and saw there are turbulences all the time when the stream is rapid.

Laminar or turbulent be the stream, for assessing the water sinking at
macroscopic level, has no relevance. The same for all the rest: hydro-
static pressure does not compress the sands on the bottom because the
hydrostatic pressure is spherically symmetric. Wet equilibrium means
water is all around, on the top it's free, bottom it's in the gravels,
but it's still water that escapes to unidirectional compression. The
materials are unidirectionally compressed by their own weight and it's
the water in between the particles that's moving, not the solid materials.
If they don't move, it's not only because of friction between the grains
of sable or gravels. They can be transported away (yes, Bernoulli law) if
the stream speed increases, like in case of floods and will be deposited
when the speed of sedimentation gets higher than the forces pushing the
solid particles away, and this has importance for cleaning up the bottom
of the reservoir where all the sediments will be deposited. No relevance
for water sinking, though.

The same for osmosis: what's important is not the pression but the
difference of pression. The same for diffusion: it's occuring between
two substances of the same phase, or if the solid substance is soluble.
The same for the rest of the deductions.

There is one point, where Mr. Frajkor is right and it's where he has
concrete informations, not his own deductions - I checked it and it's
really so: the resevoir is not hermetized, only the long canal to the
turbines. It's thanks to this surplus of hydrostatic pression that the
underground water level increased near to the reservoir. Thus, to collect
the sinking water that goes through the dam, there is a collecting
"sinking" (priesakovy) canal that creates a hydrostatic counter-pression
and creates a potential barrier to prevent outwashing of materials from
under the reservoir. The long narrow canal that brings the water from the
reservoir to the dam with turbines is hermetized.   I was there before
the dam got inundated and saw the beton on the sides and asphalt on the
bottom.

There is an interesting question: if the underground water level on the
Slovakian side increased, why Hungarians claim on their side it dropped.
I will write a couple more words about this in an another posting. I'm a
theorician and have no problems to think, but there are concrete data
it's not easy to get to.

There are much more interesting questions about Dunakiliti and possi-
bilites to increase the underground water level on the Hungarian side
but I prefer to get better documented before developing more on this.

Roman Kanala

 wrote:

: In this article, I am speaking about fluid dynamics, hydrostatic
: pression, Bernoulli law and similar uninteresting things - a warning
: to prevent people to complain - if not interested, skip it right now;-)

: From the very beginning, I have to ask myself about the usefullness of
: continuing this senseless debate over Bernoulli and water sinking.
                  ^^^^^^^^^ ?
DELETED lotsa techy stuff that DO make sense (i've kept some of the best):

: My point is that these phenomenons can be safely neglected in Gabcikovo
: case because of low speed of the stream, unless wanting to go through a
: calculus with many digits just for fun.
streams meander (their loads vary by the 'theta' angle.... gimme a break!)

: Of laminar or turbulent flow. To assess this, a huge amount of exact...
yup, esp if laminar=layered flow?

: conditions (shape of the bottom) and it's the chaos theory that gives
GREAT! chaos iz the ONLY way to doo it!

: Laminar or turbulent be the stream, for assessing the water sinking at
: macroscopic level, has no relevance.
                         ^^?
i'd say "that we know of" here!

: The
: materials are unidirectionally compressed by their own weight and it's
: the water in between the particles that's moving, not the solid materials.
what's chromatography about? it's ALWAYS stuff that moves! it's RATE is diff!

: ...
: solid particles away, and this has importance for cleaning up the bottom
                                                    ^^^^^^^^^^^?
: of the reservoir where all the sediments will be deposited.
: No relevance for water sinking, though.
kinda deterministic here! self-defined dismissing a possible density variable.

: The same for osmosis: what's important is not the pression but the
: difference of pression.
yup!

: The same for diffusion: it's occuring between
: two substances of the same phase, or if the solid substance is soluble.
not necessarily... see Eh/Ph Pourboix diagrams concerning solubilities!

: Thus, to collect
: the sinking water that goes through the dam, there is a collecting
: "sinking" (priesakovy) canal that creates a hydrostatic counter-pression
: and creates a potential barrier to prevent outwashing of materials from
: under the reservoir.

: The long narrow canal that brings the water from the
: reservoir to the dam with turbines is hermetized.   I was there before
: the dam got inundated and saw the beton on the sides and asphalt on the
: bottom.
great observation! tell more about before/after sighting!


: There is an interesting question: if the underground water level on the
: Slovakian side increased, why Hungarians claim on their side it dropped.
i DON'T understand how culture got into this "scientific" discussion?
i thought we wuz talkin about water not a Slovak/Hungarian issue... sorry...

: I will write a couple more words about this in an another posting. I'm a
: theorician and have no problems to think, but there are concrete data
                                                          ^^^^^^^^
iz that "beton" or asphalt?

: it's not easy to get to.
i am engulphed in agreement with you!

best :)
sp



: There are much more interesting questions about Dunakiliti and possi-
: bilites to increase the underground water level on the Hungarian side
: but I prefer to get better documented before developing more on this.

: Roman Kanala

"In an article entitled "Media Watch", Eva Balogh mentions with disapproval
that Gyula Horn has raised, as a trial baloon, the notion of a "wealth
tax". <etc...>"

Aside from the unfortunate fact that a lot of hu"lye people agree with
you, on what logic do you base the idea that the rich should pay a
disproportionately larger share of taxes?