At 10:41 AM 8/5/2011, Daniel Rocha wrote:
Yes, he measured the pressure. He doesn't need an instrument specific for that. You don't need an instrument for every data you want to find. For example, even in any big particle colliders you don't see all of the resulting colliding particles. You reconstruct the the trajectories and the energy and deduce what kind of collision happened.
This is total BS. Of course he doesn't need an instrument specific for that. The obvious method is to look at the temperature of saturated steam. However, Galantini concluded -- we don't know how -- that the steam was dry. Dry steam will not tell you what the pressure is.
If you have wet steam at 100.5 degrees, I did the calculations, I forget the pressure I came up with, but it was about 1.03 bar, as I recall. Galantini states a temperature of 100.1 degrees and a pressure of "ambient," which would have been below 1 bar because of the elevation of Bologna.
The statements are not consistent, and those here who are claiming that this humidity meter measurement is just fine are simply exposing strong bias. I've been looking for months. There is nothing confirming that you can use a humidity meter to measure steam quality. Zilch.
Except for Galantini's claim. Kullander and Essen seem to have made the same mistake. None of these people have explained how they did it. They have not reported the meter readings they obtained. Galantini simply reports "dry," which would be an astonishing result to anyone who understands steam engineering, making it obvious that he doesn't.
Kullander and Essen reported quite low levels of wetness by mass. Low enough to be supicious in themselves. It appears that Kullander and Essen likewise did not have steam experience, Essen has been explicit about that.
We do know that all these people used a relative humidity probe, and they read the meter in g/m^3. Somehow they converted this into a steam quality measurement. How? They have not said, in spite of multiple requests.
What is that reading? From the manual, it is absolute humidity. However, the sensor is not designed to admit liquid water at all. It is only measuring vapor. With low accuracy near 100% humidity, by the way, the manual states +/- 3.5% above 95% humidity.
