I wrote:
> That's ~500 J/s. The flow rate is 2 g/s which takes 180 J to bring to boil, > leaving 320 J, which is enough to boil about half the water. The other half > would have to overflow unboiled. For the reasons given by Storms and me I > think this is unlikely. > That's wrong. I did not mean it unlikely that the machine boils half the water. I meant to say: "for the reasons given by Storms and me I think it is unlikely that steam would emerge from the end of the hose, or that no one would notice the water is overflowing." Something that has not been clarified here is that the flow rate is rather slow; 120 ml/min. Before the water boils, when the liquid overflows, It would take a long time to fill up the hose. There would be a lot of water in there. Once it starts boiling the steam sparges in the slow moving water. I suppose it would cool down and condense by the time it reaches the end. In other words, the hose would radiate a lot of heat next to the machine, and less further on. On Saturday when I was trying to clean grout with a 1.3 kW steam cleaner, I noticed that when I turned off the trigger for a while, it soon filled with condensed water. The length of hose next to the machine remained a lot hotter than the hose close to the end, where the condensed water was. This is plastic hose, thinner than Rossi is using. The steam cleaner did not do as good a job as shown on TV. I tried it on the grill and some other hard-to-clean spots. I should have tried a food stain in the carpet. As I said, the plume of steam from 1.3 kW was puny. (1.3 kW was the rated power on plate at the bottom of the gadget. I did not measure it with an ammeter.) Anyway, the demonstration was unclear and there is not much point to trying to analyze it in detail. I cannot understand why Rossi does not do a more convincing test. - Jed
