OK, I've now conceived of how the temperature is stabilized without feedback control, and it doesn't require anything like mixed phase flow. All it requires is pressure in the reaction vessel high enough to keep the liquid flow at the boiling point (for that pressure) and transport away all the power within the heat of latent heat provided by the nearly discontinuous rise in effective specific heat of water at the boiling point.
The water pump pressure feeding the E-Cat could be very high relative to atmospheric pressure, and the pressure drop at the exit from the E-Cat could be quite substantial prior to the thermocouple, resulting in a dry -- even superheated -- steam. So my originally post problem of estimating the pressure at the output thermocouple still stands as critical in invalidating the Oct 28 demonstration. On Wed, Nov 16, 2011 at 7:23 AM, James Bowery <jabow...@gmail.com> wrote: > This is another one of those "give Rossi the benefit of the doubt" issues: > > The only way I can conceive of a temperature equilibrium in a > temperature-enhanced LENR system that doesn't have a heating element > setting its lower bounds (and heat-transport medium's phase change its > upper bounds) is to feedback from temperature to the heat-transport > medium's mass flow rate. > > If there is no such control then I can't conceive of how the temperature > is stabilized. > > > On Tue, Nov 15, 2011 at 1:36 PM, Joshua Cude <joshua.c...@gmail.com>wrote: > >> >> >> On Tue, Nov 15, 2011 at 1:18 PM, James Bowery <jabow...@gmail.com> wrote: >> >>> On Tue, Nov 15, 2011 at 11:56 AM, Joshua Cude <joshua.c...@gmail.com>wrote: >>> >>>> 2011/11/15 James Bowery <jabow...@gmail.com> >>>> >>>>> If the pressure at the output thermocouple of the Oct 28 demo exceeds >>>>> the critical pressure of steam at the reported temperature, then there is >>>>> no heat of vaporization represented in the mass flow hence in the imputed >>>>> power level. >>>>> >>>> >>>> As Stephen Lawrence has emphasized, if the fluid is all steam at the >>>> output, then the temperature fluctuation corresponds to about a 1% power >>>> fluctuation. If it is all water, then it's about 2%. Neither seems very >>>> likely given the huge range of power outputs reported over the year. >>>> >>> >>> My understanding is that Rossi's primary problem in achieving >>> self-heating was fine tuning the control of the water flow rate so as to >>> stabilize temperature, rather than relying on an internal resistance heater >>> to assist in setting the lower bound of the target range. If that is the >>> case, then we should expect to see fluctuations in mass flow rate rather >>> than fluctuations in temperature -- regardless of phase. >>> >> >> I guess that's possible, although you might expect a kind of oscillation >> in the temperature, like you get with a thermostat. Where does he describe >> this? Does he use the output temperature in a feedback loop to adjust the >> flow? I haven't seen any indication of that in any of the earlier ecats, >> and not enough of the multi-cat was shown to see any evidence for it. >> >> >> >
