Frans,
It would be a pleasure to host you for a night of beer (even though my regular drink is Scotch). Please do come and visit!! Will you be at the NFPA meeting in Las Vegas in June? I will be speaking there. And one day, I hope to walk the trails to Rome as many of your fellow countrymen have done!! I understand it is quite the experience along the way. I appreciate your contributions to the forum and to our industry. Sincerely, Cecil Bilbo Academy of Fire Sprinkler Technology Champaign, IL 845-878-4200 x138 www.sprinkleracademy.com > Date: Sun, 29 Nov 2009 03:14:43 +0100 > To: [email protected] > From: [email protected] > Subject: RE: Bilbo Velocity Formula > > Cecil, > > You really got me curious. When I had the time I would jump over and > discuss it with you and your sun over a beer! > > I guess the variables at the node in concern are > - K-value of branching-off sprinkler or branch pipe > - total pressure > - downstream flow > - actual inner diameter of the upstream pipe? > > In a previous life I studied electronics engineering. My approach to > watery networks, when I got involved for the first time, was to apply > electronic network analysis to hydraulic calculation of sprinkler > networks. Electrons through wires, transistors and other components > behave much the same as water through pipes, fittings, venturies etc. > Just different formulas. > That's how I soon found out that I needed an integral to calculate > normal pressure without iteration. The funny thing with integrals > however, is that many integrals cannot be calculated; they have to be > discovered. But once you discover an integral it is easy to prove > that it is the correct answer to the integral you were looking for. > Also, by looking at the answer, there is no way that you can tell > that the original question was to find an integral! > > So, I suppose your sun discovered a smart route to bypass the > integral-problem and found the answer otherwise. > Congratulations! > "There are many ways that lead to Rome" is a Dutch saying, but this > special "Rome" is not easy to find. > > Frans Stoop > TOS architecture & fire protection > Netherlands <[email protected]> > Tel. +31-24-324 0112 > > > At 18:46 25-11-2009 +0000, you wrote: > >Frans, > > > >Thanks for your interesting story about formulas and such. I > >started on a Tandy TRS-80 (from Radio Shack)and I know that I was > >late to the game. I must admit to being impressed by folks with a > >solid math background. I am only able to use the tools I have been > >given during my limited career, and being in the Sprinkler Industry > >has not left much time for advanced math. > > > >According to Skyler Bilbo, the young man that deduced the formula: > > > >- No integral required. > > > >- One straight formula with 4 different variables. The formula can > >produce incorrect results with ridiculously high flows and very low > >pressures. (Of a kind never encountered in the sprinkler industry.) > > > >An associate of mine in San Diego, that I consider brilliant, used > >the formula on 70 different systems that had been previously done by > >hand using the "guess and check" method we currently use in the > >industry. He reported that every calculated flow and pressure > >matched his beyond an accuracy of one-thousandth. > > > >We anticipate more peer review after submitting a report for > >upcoming editions of trade magazines. > > > >It should be recognized that the above is my opinion as a member of > >the NFPA 13 Committee on Installation Criteria, and has not been > >processed as a formal interpretation in accordance with the NFPA > >Regulations Governing Committee Projects and should therefore not be > >considered, nor relied upon, as the official position of the NFSA > >nor the NFPA, nor any of their technical committees. > > > >Sincerely, > > > > > >Cecil Bilbo, Sprinkler Geek/Teacher Dude > >Academy of Fire Sprinkler Technology > >Champaign, IL > >217-363-2460 > >www.sprinkleracademy.com > > > > > > > Date: Tue, 24 Nov 2009 14:59:42 +0100 > > > To: [email protected] > > > From: [email protected] > > > Subject: RE: Sprinklerforum Digest, Vol 4, Issue 16 > > > > > > George, > > > > > > True, it can be done without assumptions, although one needs an > > > integral to solve it. > > > The integral is of a type that cannot be calculated, but has to > > be discovered. > > > It is a lengthy formula and it works for tree type systems only. > > > With the integral it is possible to calculate directly the normal > > > pressure on nozzles, sprinklers and branch lines without "looking" > > > forward at the upstream flow. > > > In 1983 I could prove mathematically that the integral exists. In > > > 1984 I finally discovered the integral. > > > The reason that I was looking for it, was that computers were still > > > very slow at that time, so iteration required a lot of patience. > > > > > > Incorporating normal pressures in a grid or looped system can still > > > be done by iteration only (= with assumptions), although the > > > assumptions can be estimated automatically. > > > > > > That same year (1984) I used the formula for the first time in > > > hydraulic calculations for a Du Pont de Nemours plant in Holland. > > > Du Pont invited me for engineering purposes to Wilmington, where I > > > also met Mr. Howard W. Packer, member of the NFPA TC for water > > based systems. > > > At one of those trips I brought my self-built portable computer case, > > > containing a Sinclair ZX81 with a Memorex spreadsheet module (a.o. > > > peripherals). > > > Du Pont had organized a television set to act as computer screen and > > > I had changed the Sinclair from the European PAL output format to NTSC. > > > This configuration allowed us to perform computerized hydraulic > > > calculation of the deluge-systems, incorporating normal pressures in > > > the calculation. > > > The output was printed by a Sinclair printer on an aluminium colored > > > 4 inch wide paper strip. > > > > > > In those days Du Pont also had their first Intergraph computer to > > > make digital process piping layouts. > > > The Intergraph computer was so expensive that they had 3 shifts > > > operating it 24 hours a day. > > > > > > Around 1995 we shared the formula with Kevin Kimmel and Mark Lentocha > > > of FPE Software, who where our business partners at that time. > > > As far as I know FPE never used it. > > > > > > In our office we still use the formula almost every day. It is > > > embedded in a spreadsheet program. > > > We think it is too tricky to embed it in a commercial program, > > > because the user must be very well trained to distinguish in which > > > cases the formula can be used and when not. Actually it works for > > > standard tree type deluge, waterspray and sprinkler systems only. > > > When sold as a program it will probably generate a lot of helpdesk > > > requests. That's why we didn't market it. > > > > > > Today's computers are so fast that it makes hardly any difference if > > > you calculate with iteration (= with assumptions) > > > or single run only using the normal pressure integral. > > > > > > Frans Stoop > > > TOS architecture & fire protection > > > Netherlands <[email protected]> > > > Tel. +31-24-324 0112 > > > > > > At 13:24 23-11-2009 -0500, you wrote: > > > >Actually, I believe a newbie to the industry with a really smart > > father has > > > >developed a method to NOT make assumptions, but use his formula to simply > > > >plug in your values and go. I believe it will be released soon, once > > > >marketing determines how to make a buck on it. > > > > > > > >Glc > > > > > > > >-----Original Message----- > > > >From: [email protected] > > > >[mailto:[email protected]] On Behalf Of Roland > > > >Huggins > > > >Sent: Monday, November 23, 2009 12:30 PM > > > >To: [email protected] > > > >Subject: Re: Sprinklerforum Digest, Vol 4, Issue 16 > > > > > > > >I did an article on it a long time ago (around the time that NFPA 15 > > > >started requiring it). I'll see if I can put my hands on an > > > >electronic copy and email it to you. > > > > > > > >If memory serves me correctly, the challenging part is noting that you > > > >have to make an initial ASSUMPTION on how much is flowing out of the > > > >sprinkler since the velocity and flow is calculated for the pipe > > > >section upstream from the sprinkler, you then modify your initial > > > >assumption for the final result (like when using the Hardy-Cross > > > >method for calculating multiple loops by hand though it's a bit more > > > >work). > > > > > > > >Roland > > > > > > > >On Nov 22, 2009, at 5:04 PM, Miguel A. Lopez wrote: > > > > > > > > > I am trying to learn how to manually calculate a sprinkler system > > > > > using the > > > > > velocity pressure method for the NICET exam, I took a webminar on the > > > > > subject, but it did not workout for me, I still confuse with the > > > > > method. > > > > > Will someone recommends me a book that will help me? > > > > > Please respond to my E-Mail address [email protected] > > > > > I want to thank you in advance for your time and consideration > > > > > Miguel A. Lopez > > > > > > > _______________________________________________ > Sprinklerforum mailing list > [email protected] > http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum > > For Technical Assistance, send an email to: [email protected] > > To Unsubscribe, send an email to:[email protected] > (Put the word unsubscribe in the subject field) _______________________________________________ Sprinklerforum mailing list [email protected] http://fireball.firesprinkler.org/mailman/listinfo/sprinklerforum For Technical Assistance, send an email to: [email protected] To Unsubscribe, send an email to:[email protected] (Put the word unsubscribe in the subject field)
