On Wed, Nov 16, 2011 at 9:56 AM, James Bowery <[email protected]> wrote:
> > Since the effective specific heat does not remain constant with > temperature -- there is a discontinuous rise at the boiling point -- there > is a dramatic rise in the effective heat transport with temperature at the > boiling point (whatever it is for the pressure in the reaction vessel). > > I don't follow. Obviously, there is a discontinuous rise in the power transfer *as a function of fluid temperature*. The same temperature can correspond to any power transfer between 70 kW and 470 kW. But there is not a discontinuous rise in the power transfer *as a function of time*. The power transfer is not discontinuous with the temperature of the core (or more specifically, with the heating element). In fact, since the heat-transfer coefficient to steam is lower than to liquid water, the temperature of the core has to increase faster to increase the power transfer after the onset of boiling. And since the core temperature is not likely to change temperature discontinuously (in time), then the power transfer is not expected to change discontinuously with time. And yet, in all the steam conversion demos, the implicit claim is that as soon as the bp is reached, the output is dry steam. It's just not possible.
