Re: Konstantin Tsiolokvsky was wrong?!

"Spaceman" <Realspace@xxxxxxxxxxx> wrote in message news:ecudnWk3WfJCbJ3ZRVn-qg@xxxxxxxxxxxxxx

"Greg Neill" <gneillREM@xxxxxxxxxxxxxxxxxx> wrote in message
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"Greg Neill" <gneillREM@xxxxxxxxxxxxxxxxxx> wrote in message
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"Greg Neill" <gneillREM@xxxxxxxxxxxxxxxxxx> wrote in message
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It can never be relatively constant,

Why? If the fuel is fed at a constant rate and he
burn continues at a constant rate, and the pressure in
the combustion chamber is constant,

Bingo!
There is your problem,
A pressure chamber can not remain constant,
when it is not closed.
Again you seem to not even know basics
about an open or closed "system".

Hey James, when you're driving your car down the
highway (assuming that you have a car), how do
maintain a constant speed?

I hit the cruise control,
and sadly, my fuel does not stay constant

No, it wouldn't if there are hills and variable
winds. Fortunately we don't have that problem
with the empty space of our gedanken experiment.

You still burn fuel, and that is not constant
so the mass is changing so even with a constant
fuel burn, you will not have a constant speed.

You fail to understand the equation. It is specifically
taking into account the changing mass; it's the dm and
M - dm bits.

In the discussion, e is the velocity of the exhaust
gas as it leaves the rocket, as measured from the
point of view of the rocket. In other words, a
constant thrust rocket is assumed.

Oh, here we go with the frame bull***.

What? Please explain. What's wrong with measuring
the velocity that something is "thrown" at with respect
to what's throwing it? Do you have a better reference
point?

LOL
assuminga constant thrust of the rocket
is a joke.
The mass will lessen so there can not be a constant
velocity of the rocket,
and the pressure will decrease
as fuel burns so there can not be a constant fuel departure
speed.

Thrust is not velocity. Spaceman wrong again. Rocket
velocity not said to be constant (very obviously), spaceman
wrong again. Pressure in the combustion chamber *will*
be constant so long as the the fuel is delivered at a constant
rate during the burn, spaceman wrong again.

You apparently love to worship constants, that can't be
constant.

James has to fabricate erroneous issues in order to
have anything to say at all. James is almost always
wrong.

LOL

Are you now saying it is about a constant speed
of the rocket?

No, it is the speed of the exhaust from the rocket.

The speed of the exhaust can not be "constant" without a
constant pressure for such fuel.

No problem. That's what rocket engine design is all
about.

fuel does not act that way in an open full birn situation
like most rockets.

James knows nothing about rocket engines, including
fuel pumps, pressure sensors, feedback mechanisms,
control systems, etc.

In the present discussion, e is being used as the
symbol standing for the exhaust velocity with
respect to the rocket.

And it can not be constant
and especially not at the e I saw used
so far....

It is stated to be constant for the derivation,
and a constant exhaust velocity is a very good
assumption for rockets that employ controlled
burns. James is too ignorant to even check
his facts before objecting!

You are too foolish to realize such.

Prove that rocket engines cannot maintain a constant
thrust over extended burns.

It seems in your broken model
the e can be tiny and have rockets doing
amazing speeds from a drop of water being pushed
out.

James has not plugged any numbers into the trivial
rocket equation, or else he wouldn't be making
such bone-headed statements.

That's what differential equations are for.
The variable masses and velocities aren't a problem,
as they are calculated in differential form. The
only assumed constant is the exhaust velocity,
which is a good assumption for a reasonably
designed rocket (contant thrust under dynamic
control).

Greg, you are freakin moron,
There is no constant exhaust velocity, in fact
we did not even know the exhaust velocity at all,
How did you come up with it being constant
and what was your number for it?

There's no number in the derivation, obviously;
the exhaust velocity depends upon the specific
rocket, and the derivation is for the general
case. Therefore the exhaust velocity is represented
by a symbol. Are you incapable of manipulating
symbols like other higher primates?

James, explain why, specifically, you think that there
is no constant exhaust velocity. Is it just because
otherwise you'd have nothing to argue about?



Please explain precicely why the exhaust speed could
not be made constant with respect to the rocket.
Everything else in the equation are variables and
are handled as a differential equation, so they're
not a problem.

Show me how a 2 meters per second push speed
can push something faster than 2 meters per second.
(and remember this is a pushing speed , not a collision speed)

<snipped insultation physics that seems to be Gregs only physics>

You work it out. You've been spoon fed the equation,
now plug in some numbers. You're obviously typing your
posts from a computer, use it for something other than
typing lame usenet posts -- write a program to plot
the terminal velocity of rockets with various starting
masses and fuel capacities. Use the Saturn V exhaust
velocity information.

http://spider.ipac.caltech.edu/staff/waw/mad/mad3.html



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