On Sat, Jun 25, 2011 at 3:58 AM, Horace Heffner <[email protected]>wrote: > > The power is noted to be 770 W. If you assume no nuclear reaction then > that is all there is. It should only take minutes to reach equilibrium. >
True. Some say it's really 800W (230V), but still only minutes, as you say. I was describing what might happen if the power continued to increase. > After that, as the power increases further, more of the water changes phase > to absorb the additional heat, but the output will still be a mixture of > steam and mist at the boiling point. The fraction of dry steam will increase > as the power increases. If it were ever to reach 5 kW (or so), then as the > water passes the reactor, it is all converted to steam. > > That transition from 600W to 5 kW would have to correspond to an increase > in the temperature difference between the reactor and the water by the same > factor of 8 (in this case). That would take time, which can be estimated by > the time it takes to go from zero power transfer to 600W, and corresponds to > hours. Yet Rossi and his believers assume that at the moment the bp is > reached, or very soon thereafter, there is a magical transition from 600W > transfer to 5 kW transfer. It makes no sense. > > > I don;t see why you think it makes no sense. If you place a 5 kW heater > element in the device and turn it on then 5 Kw is being delivered instantly. > > But that clearly *doesn't* happen when the heating element is turned on at the beginning. There is a rather gradual gradient in the output temperature as the thing heats up to the boiling point. That shows there is a thermal mass there. The thermal mass will still be there no matter where the heat comes from, and even if the water temperature is already at the boiling point. If there was a step change to the boiling point when the 800 W is applied, then I would agree with you. But there isn't. > It takes very little time, seconds, for the heat flow to go through metal > walls and be delivered to the water. > It takes more than seconds. We know this because it heats up gradually at the beginning. Now, if the 4 kW from the reactor is turned on in an instant, the gradient would be steeper to be sure. But it also has much more of temperature increase necessary to reach dry steam. So, it should still take at least the same amount of time to boil all the water as it takes to reach boiling. But there is no indication that it does turn on instantly. In at least two of the runs, Rossi claims ignition happens before the bp is reached. In fact they point to change in the gradient when that happens. The gradient is steeper, but not by a factor of 7. The real problem is the question of just how much energy is delivered by the > E-cat and when. Only good calorimetry can determine that. > Can't disagree with that. > Any liquid filling the hose will be blown apart by the steam forming behind > it. > > > This is nonsense. At 770 W the liquid will simply accumulate in the hose > and then be driven out by steam pressure. As I said earlier, a transparent > hose should offer some useful information, one way or the other. > To make another analogy, in steam radiators, loud bangs heard are from water collecting, and then being driven against the metal by steam pressure behind it. At 800W, it may not be that violent, but yes, a clear hose would be nice. I doubt that's gonna happen. > > Note that the pump rate is small, on the order of a few cc per second, so > it can take a while to fill up a hose held upright into the air, even if the > device itself is full of water - which probably can not happen due to > percolator type effects. > > Right, except I don't find the comparison to hot beverage makers very > useful because this system has a clear inout and output, and a pump that > keeps the flow rate constant. Maybe an espresso maker might be better, but > I'd rather just think about the actual device itself. > > > Nonsense! Percolators (at least some) cycle the liquid right back to the > boiling area. Not much different from a pumped flow of water, other than > the inlet temperature. > Except the flow is driven by the process alone. There is no pump regulating the flow. That's a difference. > It is the *principle* of the lifting power of steam bubble expansion, > wherever it occurs, and its effect on water in the chimney that is key to > understanding how the calorimetry can be so far off. Personally I think > "percolator effect" provides a useful descriptive term to which most anyone > can relate. Since I conceived of this explanation, I certainly feel free to > call it whatever I chose. > Percolators are pretty rare these days. And even when they were common, not many people could relate to how they worked. > > Note also that if the input power is reduced (cycled) momentarily to about > 600 W that pure 100 °C water will be eventually pumped out the exit port. > The controller box is doing *something*, which Rossi explicitly states is > related to temperature and pressure. > I see no evidence it is doing anything but providing constant current. There is no indication of feedback of any kind. But I admit, it's possible. Not knowing what that something is implies a need to do an overall > calorimetric energy balance for each experiment. Until that is > accomplished this is all useless talk from the peanut gallery. > Obviously. I have no delusions that this discussion is useful. The reaction chamber is 50 cc on some models. The water jacket and flue may > be less than that or more. If they are 50 CC too then at 2 cc/sec they will > fill up with 100 °C water in 25 seconds if the power is about 600 W and flow > about 2 cc/sec. > Well, it is already filled. So the water is replace every 25 s. > Slightly more power than 600 W and the steam bubbles formed will create a > powerful percolator effect, pushing all the liquid water forward, and the > water near the top of the chimney out the exit port. I don't see why > "overflow" is not an apt term for that, > Because the water is flowing through the chimney and into the hose before boiling begins. It flows into a hose. That's not overflow. It's just flow. No one called it overflow when it wasn't boiling. Why is is overflow when it is boiling. But quite right. This is quibbling, with a capital Q.
