On 08/24/2016 12:03 AM, David Roberson wrote:
As I have stated, if the steam is truly dry then plenty of power is
being supplied to the customer. If the ERV is mistaken that the steam
is dry then I.H. is likely correct.
If everyone accepts that the true pressure of the steam is atmospheric
while the temperature is 102.8 C then it is dry.
Unless there's some active feedback mechanism keeping the temperature of
the effluent between 100 and 103 C, it's hard to believe the effluent is
dry steam. The heat capacity of steam is so small compared with the
latent heat of vaporization one would expect the temperature of (dry)
steam in the closed system to be driven well above boiling -- not just
barely over it.
This has been the problem with Rossi's steam demos since the beginning:
There is no feedback mechanism to keep the temperature barely above
boiling, yet it never goes more than a couple degrees above. Either
there's feedback nailing the power output to the level needed to /just
exactly/ vaporize the water (with essentially no heat left over to
superheat the steam), or there is feedback nailing the water flow rate
to the be just fast enough to consume all the heat from the system in
vaporizing the water, or there is a miraculous coincidence between the
heat produced and the water flow rate.
We /know/ there's no feedback controlling the flow rate, because that
was rock steady.
No mention has ever been made of any feedback mechanism fixing the
reaction rate to the steam temperature, so short of fantasizing about
something Rossi never said he did, we have no reason to believe such a
thing exists. In fact we don't even know that the reaction (if there is
a reaction) can be controlled with the precision needed to keep the
output temperature so close to boiling -- and we also have no reason to
believe anyone would even /want/ to do that.
So, the only conclusion that makes sense in this situation is that the
"feedback" keeping the temperature almost exactly at boiling is provided
by water mixed with the steam, and that consequently the steam must be
very wet.
But that is the root of the problem; both parties do not agree that
this is true. Only one can be right in this case. Also, there is no
law of nature that ensures that what the ERV states is true. He may be
confused by the location of gauges, etc.
AA, Engineer48 claims that the pumps are all manually set and not
under automatic control according to his picture. If true, that would
eliminate the feedback level control that was discussed earlier. It
is my opinion that some form of automatic level control is required in
order to produce a stable system that prevents liquid filling or dying
out of the CATS. This is an important factor that both of the parties
should address.
Dave
-----Original Message-----
From: a.ashfield <[email protected]>
To: vortex-l <[email protected]>
Sent: Tue, Aug 23, 2016 10:59 pm
Subject: Re: [Vo]:Interesting Steam Calculation
Apparently the ERV measured 102.8 C @ atmospheric pressure. That is
dry steam.
That implies the customer used steam at a negative pressure.
On 8/23/2016 8:50 PM, Bob Cook wrote:
Dave--
The steam table indicates a condition of equilibrium between the
liquid phase and the gaseous phase of water. If the conditions
are 1 bar at a temperature above the 99.9743 there is no liquid
phase in equilibrium with the steam (gas) phase. The gas is phase
is at 102 degrees and is said to be super heated.
The steam tables tell you nothing about liquid phase carry-over in
a dynamic flowing system. Normally there would be a moisture
separator in the system to assure no carry-over.
Bob
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*From:* David Roberson <[email protected]>
*Sent:* Monday, August 22, 2016 9:27:19 PM
*To:* [email protected]
*Subject:* Re: [Vo]:Interesting Steam Calculation
Dave--
Where did the pressure of 15.75 psi abs come from? I thought the
pressure of the 102C dry steam (assumed) was 1 atmos.--not 15.75 abs.
I think your assumed conditions above 1 atmos. were never measured.
Bob Cook
Bob, I used a steam table calculator located at
http://www.tlv.com/global/TI/calculator/steam-table-pressure.html
to obtain my data points.
According to that source, 14.6954 psi abs is 0 bar at a
temperature of 99.9743 C degrees.
At 102 C degrees the pressure is shown as 15.7902 psi absolute.
Also, at 15.75 psi abs you should be at 101.928 C. I must have
accidentally written the last digit in error for some reason.
Does this answer your first question?
You are correct about the assumed pressures above 1 atmosphere not
being measured directly. I admit that I rounded off the readings
a bit, but the amount of error resulting from the values I chose
did not appear to impact the answers to a significant degree. In
one of Rossi's earlier experiments the temperature within his ECAT
was measured to reach a high of about 135 C just as the calculated
power being measured at the output of his heat exchanger reached
the maximum. At the time I concluded that this must have occurred
as a result of the filling of his device by liquid water.
I chose 130 C for my latest calculations mainly as an estimate of
the temperature within the ECAT modules. The higher pressure
(39.2 psi absolute) was the value required to keep the liquid
water in saturation with the vapor. Rossi is using a feedback
system to control the heating of his modules and that requires him
to operate each at a few degrees above the output temperature(102
C?) as a minimum. There is no guarantee that he regulates them at
130 C as I assumed, but that temperature was consistent with
having a ratio of vapor volume to liquid volume of nearly 100 to 1.
Of course I could have raised the ECAT temperature to get a larger
ratio of flash vapor to liquid water at the output stream.
Likewise, the ratio would drop if a lower temperature is assumed.
The 130 C appeared to be near to his earlier design, and I had
to choose something. Do you have a suggestion for a better
temperature or pressure to assume?
Dave
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