On Sun, Jun 26, 2011 at 3:23 AM, Joshua Cude <[email protected]> wrote: > > > On Sat, Jun 25, 2011 at 9:11 PM, Jeff Driscoll <[email protected]> wrote: >> >> On Sat, Jun 25, 2011 at 8:58 PM, <[email protected]> wrote: >> > In reply to Joshua Cude's message of Fri, 24 Jun 2011 16:20:48 -0500: >> > Hi, >> > [snip] >> >>I was talking about running it above boiling, but way below the level >> >> needed >> >>to boil it all. Different thing. And it's easy. The power can range >> >> within a >> >>factor of 7. In this case, anywhere between 600W and about 5 kW. >> > >> > BTW (the latent heat of steam) / (the heat energy required to bring >> > water to the >> > boil) is a factor of about 6.7 (depending on starting temperature of >> > water), and >> > curiously close to the COP Rossi claims to be aiming for. >> > In short, if virtually none of the water were converted to steam, and he >> > was >> > assuming that it all was, then it would neatly explain the conversion >> > factor he >> > is claiming. >> > >> >> You might be thinking of another scenario - but if I'm guessing what >> you are saying then the best anyone could do is about 1.86 to 1 ratio. >> But this assumes that any liquid hot water needed to cool water vapor >> in a heat exchanger is included in the calculation (otherwise the >> ratio would be worse, less than 1.86 to 1). I did this calculation, >> shown below, weeks ago. [...] >> > > There is no need for heat exchangers to arrive at the ratio of around 7. The > argument goes, that if the water starts at 10C, then the amount of heat > required to vaporize 1 g is 90 + 540 = 630 cal. The amount of heat required > to bring it to the bp is 90 cal, and the ratio is 630/90 = 7. (Different > starting temperatures give slightly different ratios)
Why would you divide the energy to vaporize 1 g of water (starting at 10 C) by the energy to heat it from 10 C to 100 C (liquid)? Seems random to me. I wrote out a whole scenario with (I thought) clear steps. Give me your reasoning and steps. > These two scenarios result in the same quantitative data reported in one of > Rossi's steam producing demos, because he only reports temperature, and > input flow rate. So the same data is consistent (in Krivit's run) with 600W > and with 5 kW. > Rossi does not provide quantitative evidence that it should be closer to, or > at, the high end of that range. He only makes pronouncements based on things > like visual inspections, or unreported RH measurements, which indicate > nothing. > Now, of course, the fact that there is some steam, means it is not at the > bottom of the range either, but in the videos where he shows the steam, it > is not impressive.
