Crispin and list See inserts below.
On May 7, 2013, at 1:35 PM, "Crispin Pemberton-Pigott" <[email protected]> wrote: > Dear Ron > > >I am disappointed we have no section in 4.2.2 to look at. > > Protocol analysis is slightly more complicate than that. RWL1: shall we best assume that we will not hear about 4.2.2, and should stop asking? > > >I am no expert in this topic, but it seems to me that it makes no difference > >whether the reporting says 4.9 or 5.0. > > That is because you view the numbers are being very similar and you go on to > describe the difference as 2%. > RWL2 : Nope. There are two 2%'s under discussion. Mine was the > difference between. 44 and 46% below. I am advocating that if you think the > 4.9 and 5.0 numbers is confusing, report both. > > If the answer was 44%, have I a right to demand another test, since I > > thought it was going to be 46%? Eventually there could be millions of > > dollars riding on this sort of 2% difference. (45% is the dividing line > > between groups 3 and 4). > > When we are discussing conceptual problems, you cannot be distracted by the > numbers, you must stick to first principles. The numbers will come later. You > do not start by picking methods of convenience, you start by doing things > correctly whether the numbers are similar or not. RWL3: I am still waiting to hear the first "conceptual problem". > > >I care only that both numbers 4.9 and 5.0 are reported and the energies > >involved are done correctly. I care especially that energy in char is not > >treated as the same sort of loss as what slipped past the pot which started > >with 5 liters. > > The step immediately after deciding on what the mass of water boiled is the > calculation of the ‘specific fuel consumption’ based on that water quantity. > If you divide by the wrong number, you get the wrong answer every time. RWL4: So divide by both and the average and report all three. I very much doubt the relative rankings of stoves by a tenth of a percent. If you disagree, give us a numerical example that impacts relative rankings of stove types. > If the 4.9 was instead 4.5, the error is much larger, do you agree? RWL5 > > >You ask at the end: "Is this cognitive dissonance or conceptual error?" > >I say this is neither. The question is, did the test you described give a > >reasonably close approximation of heat transfer that was useful in > >separating stoves into four groupings. > > It is a conceptual error to use 4.9. If water is missing, then it was either > boiled and evaporated, or else it leaked out. Water does not ‘boil’ by itself > or get boiled with energy that did not come from the fuel burned. As any > practical scientist will tell you, the mass of water boiled was 5 kg or 5 > litres because it is a fact and not subject to interpretation. > > >I suggest we have better things to than debate this sort of topic. > > I suggest you look a lot more closely at the concepts embedded in the WBT > before sweeping anything aside. > > The Simmering phase of the WBT (presently called the ‘Low Power phase’ as a > way of evading the fact that the IWA participants called for and approved the > removal of all simmering in stove tests) has a metric that is ‘specific’, > meaning the emissions are given per unit of water simmered. > > When simmering, the mass of water at the beginning and at the end is > substantially different – often a litre. Here is an actual example: Beginning > of simmering, 4.8 litres. End of simmering, 3.8 litres. Which number should > be divided into the mass of fuel burned? Which should be divided into the > mass of CO emitted? 5.0, 4.8. or 3.8? How do you get a specific emission > number if the mass simmered changed during the evaluation? Is it even > conceptually possible to get such a figure? What exactly is the aspect of > performance being investigated when the question is being posed? > > >An ISO process is underway. > > The ISO process has not yet commenced. One structure has been created. When > it does, someone will form a committee and all interested countries will be > invited to participate. If this does not happen you can expect to see > resistance because the whole point of an ISO process is that the affected > parties are consulted. There are 4 fast tracks for creating an ISO standard. > If the consultation portion is omitted, you can expect there will be > problems. There is at least $500m available for stove projects at the moment > and no one wants any of it compromised by a controversial test method or > questionable performance targets. > > >We can point out big errors, but your example of 4.9 vs 5.0 doesn't rise to > >that level for me. > > That is because you are not approaching the problem conceptually and that is > why conceptual discussion should take place before mathematical discussion > (of which we have had plenty). If a lot of time is invested detailing the > mathematics of an erroneous concept it will have been wasted. > > >Put that in energy efficiency terms that matter, and we should all want to > >continue. I repeat, though, that approach 4.2.2 is where the big league > >action (baseball jargon) now is. > > Actually there is a lot more going on internationally than the discussion > about 4.2.x. In fact there is very little discussion going on in open court > about 4.2.x. There are a little groups working behind the scenes. In order to > create some progress on conceptual matters and to garner public input on a > real national standard I have been bringing questions to this forum to get > ideas and concepts discussed because it is the largest. I thank everyone for > all input on these issues. Some write privately of course. > > As far as I know, only one national standard has been independently reviewed > by competent experts and approved for comparative (not absolute) performance > determination. I hope that will soon rise to two. The WBT 4.x.x is not one of > these though it easily could be reviewed when it is ready. > > Consider this: if the WBT is pressed into service as an ISO standard without > being reviewed, some nation, wanting to know if it holds water enough to > suspend their nation’s people from its beam, will have it reviewed. Suppose > it contains significant conceptual, mathematical or procedural errors? What > then? Word will get around. Other standards will be drafted and used instead. > Why waste time? > > What if it is culturally irrelevant? What if 90% of the cooking people do is > not represented by water boiling and simmering (assuming they can keep the > name ‘simmering’ out of the simmering portion)? > > This is not a time for playing games. If you want to make comments on the > validity of test results you have to understand the ideas and the performance > metrics. Fortunately there are some very cool heads working on this right now. > > Regards > Crispin > > > _______________________________________________ > Stoves mailing list > > to Send a Message to the list, use the email address > [email protected] > > to UNSUBSCRIBE or Change your List Settings use the web page > http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org > > for more Biomass Cooking Stoves, News and Information see our web site: > http://stoves.bioenergylists.org/ >
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