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Digital manometer

Posted: Fri Sep 09, 2016 4:08 pm
by Racerrob66
I am building a flow bench for racing kart engines and would like to use a digital manometer for the differential pressure and calculate in excel instead of the inclined manometer. I am having trouble figuring out what the formula would be for this. I have done a lot of searching on the net and not had much luck. Any help you could give would be much appreciated.

Re: Digital manometer

Posted: Sat Sep 10, 2016 11:07 am
by 86rocco
Have a look at the spreadsheet I've posted HERE, included on that spreadsheet is an explanation of the math used. It should give you what you need to make your own spreadsheet.

Re: Digital manometer

Posted: Sat Sep 10, 2016 3:29 pm
by Racerrob66
Thanks I found it last night and used the formulas in a new sheet it works awesome. Thanks for sharing that sheet!

Re: Digital manometer

Posted: Sat Sep 10, 2016 5:07 pm
by 86rocco
You're welcome, I'm glad it helped.

I'm a little bit of a math geek, I'm of the opinion that everyone who builds a flowbench should first gain a good basic understanding of the underlying math. That goes a long way to answering many of the beginner's type questions and helps immensely with set-up and troubleshooting. And what you're doing with your spreadsheet, is a good way to build that understanding. I hope you'll share more of your project with us as it progresses.

Re: Digital manometer

Posted: Sat Sep 10, 2016 5:21 pm
by 1960FL
Ed that is so well stated, thank you for you continual contribution to the forum.

Rick

Re: Digital manometer

Posted: Sat Sep 10, 2016 8:37 pm
by 86rocco
Thanks Rick.

I apologize in advance, I'm going to go on a little bit of an off topic rant here: It drives me nuts when people say they found the math they learned in school irrelevant, either they weren't paying attention or they had terrible math and science teachers, I can't think of anything that's more universally relevant than math. There's no scientific or engineering discipline that isn't utterly and COMPLETELY dependent on math. Math is the language of the natural world, it's everywhere, in everything, every second of every day. Anyone that can't see that, needs to go outside, look around, open their eyes, ears and mind, and start asking questions.

Re: Digital manometer

Posted: Sun Sep 11, 2016 12:03 am
by storm
Just a response to the off topic.
86rocco wrote:I can't think of anything that's more universally relevant than math.
What about basic respect for others as human beings?
I'm qualified to teach K-12 (Humanities in High School) and honestly maths can be fudged, I have taught years 11-12 how to do it with statistics. JMHO .

Re: Digital manometer

Posted: Sun Sep 11, 2016 1:04 am
by Racerrob66
I would be glad to share the build here. i plan to use 4 inch pvc like the ez flow from performance trends and a usb data acquisition from data q. i have used the data q setup on my dyno and it worked out well. Here is the sheet i made using your formulas

Re: Digital manometer

Posted: Sun Sep 11, 2016 10:20 am
by 86rocco
That sheet looks really good.

Re: Digital manometer

Posted: Sun Sep 11, 2016 10:20 am
by 86rocco
storm wrote:Just a response to the off topic.
86rocco wrote:I can't think of anything that's more universally relevant than math.
What about basic respect for others as human beings?
Perhaps but sadly, unlike math, it's not ubiquitous.