Prominent Gamma/L 0232 Flow Rate Test


  • If I look closely at the diagrams of several Prominent pumps, then they are sometimes made up of three straight lines, with the slope rising from right to left.

    This indicates a somewhat non linear effect.

    Also for some Prominent low pressure pumps the curves are running to .5 bar. The diagrams of those pumps clearly show that the at lower pressures the rate is increasing faster then for the higher pressures.

    What the actual effects are for the pump type used in Doral is difficult to predict. So I look forward for the results of Alan's test.

    I hope Alan will also repeat the test with an added recirculation pump as was said to have been used in Doral because it would show the influence of adding such a pump.


  • IHFB. While Smith was less careful than I would be you don't expect a metering pump to have flowrate varying that much with pressure. As I (linear extrapolation from manufacturers data) and Nigel (working out stroke rate * stroke volume) both come to nearly the same figure, and this is 50% away from what is needed for Penon's data to make sense, Smith's simplistic analysis looks a correct first pass approximation.


    Only somone with an agenda (you) would call it wrong.


    Most people omit error bars when making engineering statements. It is OK, as long as there is an implicit "this is approximate because I have not done an error anlysis". In this case, as was plausible given the figures, a more exact calculation has the same import.


    I'll change my tune if Alan finds different.

  • If I look closely at the diagrams of several Prominent pumps, then they are sometimes made up of three straight lines, with the slope rising from right to left.

    This indicates a somewhat non linear effect.

    Also for some Prominent low pressure pumps the curves are running to .5 bar. The diagrams of those pumps clearly show that the at lower pressures the rate is increasing faster then for the higher pressures.

    What the actual effects are for the pump type used in Doral is difficult to predict. So I look forward for the results of Alan's test.

    I hope Alan will also repeat the test with an added recirculation pump as was said to have been used in Doral because it would show the influence of adding such a pump.


    Show us such a graph (linked) for a solenoid pump and I'll comment. I think you are talking out of your hat because P's graphs above are beautifully linear and there is no mechanism for more liquid than stroke rate * stroke volume to transfer.


    The only issue would be if the manufacturers max stroke rate could be broken.

  • We have some native German speakers here. What does 'DOSIERLEISTUNG' or 'DOSIER LEISTUNG' suggest? Minimum flow rate, maximum flow rate, or even 'minimum maximum' as some have suggested? 'DOSIERLEISTUNG' is what's on the nameplate of the the meter but the pump manual which is in English refers to it as 'Minimum pump capacity at maximum back pressure'. This and the fact that they use the word dose to me suggests it's a minimum pump rate for the maximum back pressure and as the back pressure goes down the pump rate goes up.

  • Ok, it seems appropriate for anyone interested in making Bold Predictions, to do it now, before the experiment commences.


    Here are my Bold Predictions:

    based on the manufacturers data, provided by Para, Nigel's rate * volume calc, and allowing AF measurement error, betting all the Quatloos I begged off IHFB, I boldly predict the resulting observed maximum volume rate will be less than 42 l/h.


    Further, I predict (but with no remaining quatloos to bet) that any amount higher than 37 l/h will be characterized by IHFB as proof that Smith was both wrong and malevolent with his 32 l/h statement, despite the fact that it came from the model faceplate rating under conservative conditions, and despite the fact that a number less than 42 l/h still supports Smiths conclusions contradicting Rossi's claims, which require at least 59 l/h.


    Why 42? Look at the manufacturer's graph and Nigel's calcs, add a huge experimental error factor, and remember the answer to the ultimate question raised by galactic hitchhikers.

  • Thanks, having read the report I'm now more sympathetic to Smith, there was no indication of system back pressure so completely reasonable to go with the 2 bar in the pump as a first guess.


  • Alan Fletcher and IHFB,


    All jousting and jesting aside, as a researcher I sincerely appreciate you taking the time to answer this question in a robust, objective, open and sharable way. It's quite refreshing and a service to us all.


    And IHFB, sincere thanks to you for backing this effort financially. For what it's worth, you're both the ultimate winners on this issue, regardless of outcome, IMO.

  • Further, I predict (but with no remaining quatloos to bet) that any amount higher than 37 l/h will be characterized by IHFB as proof that Smith was both wrong and malevolent with his 32 l/h statement, despite the fact that it came from the model faceplate rating under conservative conditions, and despite the fact that a number less than 42 l/h still supports Smiths conclusions contradicting Rossi's claims, which require at least 59 l/h.


    You ought to remember who lent you those quatloos. X(


    You are right, Smith was wrong, and possibly malevolent. I say that because there is a pattern of misdirection in his report, some of which I've pointed out before. He said nothing of "conservative conditions." He said nothing of error margins, back pressure, or any qualifying language whatsoever. He called it a maximum when there is nothing in the specs or manual to suggest it. In fact, they state the opposite. I might end up generously marking it up as a just a big mistake, but I'll make that determination once we see Alan's numbers.


    At the end of the day, if they were mistakes, it appears that they cost IH some leverage during the settlement negotiations.