Sunday, December 18, 2011

The Oil Drum, thread 1

Thread at The Oil Drum,

This thread is a fairly lengthy discussion, and it covers a wide range of topics, including specific calculations of isotope ratios, various scams that have been perpetuated in the past, the energy required or released by different reactions, the relative merits of some of the explanations that have been offered for LENR (including Widom-Larsen), and the economic implications if Rossi's device were to turn out to be legitimate.  One of the participants was a contemporary of Fleischmann and knew him personally, and many of them had attempted to carry out their own Pd/D replications after the 1989 announcement.

There was an interesting discussion of whether H+Ni -> Cu-63 is endothermic or exothermic.  The conclusion was that it is probably significantly exothermic in this case.  An important point related to the atomic mass of copper-63, which was subsequently the topic of a question on physics.SE.  There are two numbers that have been given for the mass of copper-63, one of which would make the reaction endothermic and the other exothermic.  The heaver mass appears to be in error.  The participants calculated the mass decrease to be .0061 GeV/c^2, or 6 MeV, which would be a significant amount of energy released into the system.  A poster mentionend that the ratio of nickel-62/nickel-64 is important, and that Rossi claimed to be using enriched nickel.  A point mentioned in passing was that the rates of decay of some elements are not always constant.  In the course of the discussion someone made use of Wolfram Alfa to carry out a computation of the resulting mass of a reaction.

One of the participants researched and taught quantum physics at Oxford for two decades.  He had met Focardi and believed that the chances that Focardi and Rossi were perpetuating a scam were small, whatever else could be said of the E-Cat.  He believed that there might be something that is actually happening in the device.  This is his summary the key detail of a paper by J.S. Brown that he cites in support of a possible fusion reaction:
The author doesn't actually make the key point very clear, but the reason why he predicts fusion is because in the near zone, the dipolar attraction pretty much cancels the monopole repulsion.  You are correct that this is a negligible effect and you still have one H in each interstitial cell.  There is nothing to see from a classical chemical perspective.  But, crucially the (classically non-existent) tails of the quantum gaussians will run into each other without the rapid attenuation you get normally due to the e^2/r monople repulsion.  Geddit ? 
Various examples of bad science were discussed at different points:  Blacklight Power, Terawatt Research, Steorn's Orbo Technology, Scalar Waves, Deflagration Guns.  One poster compared the consistency of Focardi's explanation since 1994 to that of someone offering a consistent prediction over time for the coming of the Rapture.  A link was given to a 2009 interview of Gary Taubes, who has written a book on the premise that cold fusion is an example of bad science.

There were some interesting back-of-the-envelope calculations on the economics of Ni-H power production if one proceeded from the figures reported by Rossi and Focardi.  One participant said that 2.5 g  nickel would yield 250 kWh, enough for the needs of one living a western lifestyle each day, and that it would not significantly diminish the supply of nickel over time for such power to be provided in mass quantities.

The overall tone of the thread was balanced.  Some people were clearly skeptical, while others were less so.  One of the more skeptic participants had this to say about the 1989 Pons and Fleischmann experiments early on in the thread:
As it turned out, there was no such effect and no actual fusion.  Fleischmann and Pons had just discovered some kind of weird chemical reaction that made it looked like fusion was going on, and their continuing attempts to promote it just amounted to self-delusion.
I can appreciate that people will differ on the 1989 results, but I find this level of confidence that Fleischmann and Pons were wrong a little difficult to understand.

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