On Fri, Jun 24, 2011 at 3:08 PM, Jouni Valkonen <[email protected]>wrote:
> 2011/6/24 Joshua Cude <[email protected]>: > > As soon as it starts boiling, things get very turbulent. Steam is 1700 > times > > the volume of water for the same mass, so it's gonna push things around. > > It's gonna push all the water ahead of it out, and convert the unboiled > > water behind it to a fine mist. If 1% of the water (by mass) changes > phase, > > the fluid is 95% gas, with a fine mist entrained in it. This looks like > > steam, and that's Rossi's ace in the hole. > > I do not know how many times you and abd have been told that the > measured boiling point of water is 99,7 °C. Therefore if there is mist > mixed into dry steam, it will reduce the steam temperature below > 99,7°C. But this is not what is observed, but steam temperatures that > are above 100,1 °C. You really should not ignore the last decimal > digit in the thermometer readings, because it makes all the > difference, > > It is not the temperature reading that convinces me it is at the boiling point, it is the fact that the temperature is so perfectly flat. If the steam were dry, its temperature would be free to increase, but it never does. In all the experiments, at various different flow rates and input powers, when boiling is reached, it stays flat. The actual value of the bp depends on pressure (which could be slightly elevated inside the conduit because of the production of steam and pressure from the pump), and on impurities, and on the exact placement of the probe (in relation to the heater). (I suspect the last point is the reason the temperature is slightly different (but always flat) in the different experiments: 101.6 in some 100.1 in others. If Rossi wants to use the fact that the temperature is above the bp as evidence for dry steam, then reduce the flow rate a little, and let the temperature go to 110 or 120C. He never does this.
