[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 483: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4752: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4754: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4755: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4756: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
Tractorsport Flowbench Forum Archive • View topic - test results

test results

Pitot Style Bench discussions

Postby gaz » Mon Dec 20, 2004 10:06 am

I made an excel file for calculating flow CFM. Now I'd like to compare my theoretical results with somebodys real life results. Could anybody give me his test results (ID of pipe where annubar is, velocity pressure[inH2o] and the calculated CFM)
Is it normal (on annubar bench) that to get 200CFM with 2" tube the velocity pressure on inclined manometer has to be ~8"H2O vertically measured!?
gaz
 
Posts: 21
Joined: Thu Oct 28, 2004 6:41 pm
Location: Estonia

Postby 2seater » Sat Jan 08, 2005 1:02 am

I asked this same question before I started working on my annubar bench. It's not done but I did get it put together enough to run a test to see if I had any major problems. I saw 13.5" of water column on my inclined manometer with the 2" flow tube, or about 331 cfm @ 28" depression. My inclined is designed for a maximum of 15". This was with five of the six motors running. Flow tube is 42" long with the annubar placed 2/3 of the distance from the inlet end. The length was picked to allow the 3" flow tube to be interchanged with the 3" flow tube butted tight to the 3" adapter stubs on each end for a total length of 48" of 3". One single static pickup is placed 1/2" in front of the annubar and 90* from the annubar axis. The 1.5" and 2" flow tubes are chamfered to a knife edge at the inlet end to match the rubber Fernco coupling reducer angle for a smooth transistion. The readings are dead stable using Marvel Mystery oil (.83 sp. gravity) for the manometer. The maximum reading obtained with six motors running @ 28" depression was 630 cfm through the 3" tube @ 9" w/c on the inclined. The readings will need to be verified as it seems a little high, but it was quick and dirty test. :)
2seater
 
Posts: 106
Joined: Thu Sep 23, 2004 9:18 pm

Postby RRBD » Sat Jan 08, 2005 1:08 am

Gaz,
It would be cool if you could post your excel file, I know I'd like to see it

Scott
RRBD
 
Posts: 51
Joined: Thu Apr 15, 2004 11:09 pm
Location: MINNESOTA

Postby gaz » Sat Jan 08, 2005 4:11 pm

thanks for the feedback.
RRBD you can download my "masterpeace" . and ofcourse I'm waiting for suggestions and questions because I dont say that its 100% correct.
gaz
 
Posts: 21
Joined: Thu Oct 28, 2004 6:41 pm
Location: Estonia

Postby gaz » Sat Jan 08, 2005 4:14 pm

sorry the previous link doesnt work.
gaz
 
Posts: 21
Joined: Thu Oct 28, 2004 6:41 pm
Location: Estonia

Postby jim fuchs » Sat Jan 08, 2005 10:07 pm

Marvel Mystery oil (.83 sp. gravity) for the manometer.so if i use this in my flowbench it shoulds not freeze right . also what do i need to change thes to 28 inchs of water when using this oil jim
jim fuchs
 
Posts: 13
Joined: Sun Dec 05, 2004 7:40 pm
Location: iowa

Postby 2seater » Sun Jan 09, 2005 12:34 am

2seater
 
Posts: 106
Joined: Thu Sep 23, 2004 9:18 pm

Postby gaz » Mon Jan 10, 2005 11:27 am

2seater: I did some calculations with your given results (13,5 inH2O inclined and 2" tube with ID~1.81") and I got only about 264 cfm?! I wonder what others have to say about that.
Do you recalculate the reading of your inclined manometer to get the vertical pressure difference (vpd).
vpd=L*sin(a) ,where L-is the reading on inclined manom. and a-is the degree of inclination of the manometer.

p.s. I found some mistakes on my excel sheet and repaired them.
gaz
 
Posts: 21
Joined: Thu Oct 28, 2004 6:41 pm
Location: Estonia

Postby 2seater » Mon Jan 10, 2005 10:24 pm

2seater
 
Posts: 106
Joined: Thu Sep 23, 2004 9:18 pm

Postby gaz » Tue Jan 11, 2005 4:53 am

Thanks 2seater the ID of the 2" PVC tube in Europe and in America seem to be different. I did my calculations according to "euro PVC" with ID ~1.81 inch. With 2.05 inch ID my result came 336 cfm in normal conditions (air temp 70K and airpressure 29.9inHg). Now I now my excel sheet could produce results that are OK.
gaz
 
Posts: 21
Joined: Thu Oct 28, 2004 6:41 pm
Location: Estonia

Postby 2seater » Tue Jan 11, 2005 10:16 pm

Yah, that's a pretty substantial difference in diameter. If I plug in the same 29.9"hg and 70*F. I get 337.84 cfm using .02292 sg.ft. for the 2.05" id pipe. Not a big difference, but I'm trying to learn too. :D
2seater
 
Posts: 106
Joined: Thu Sep 23, 2004 9:18 pm

Postby Ti-Beu » Sun Jan 16, 2005 12:28 am

Dont forget to take off the area of the annubar from the inside area of the test pipe. ???
Ti-Beu
 
Posts: 1
Joined: Wed Dec 29, 2004 1:51 am
Location: CANADA

Postby bruce » Sun Jan 16, 2005 12:00 pm

Interesting thought, if the velocity profile in the pipe impacts the front of the annubar does the area behind the impact point need to be accounted for in CFM calculations?
"There is no more formidable adversary than one who perceives he has nothing to lose." - Gen. George S. Patton
bruce
Site Admin
 
Posts: 1638
Joined: Sun May 09, 2004 12:17 pm

Postby 2seater » Sun Jan 16, 2005 11:48 pm

That is an interesting conjecture? I would like to know that answer myself. My logic says it shouldn't matter, since the air flow velocity is measured on the incoming side, just slightly ahead of the restriction caused by the annubar. The annubar itself is a small restriction, but it should just reduce the total flow capability, through the whole system. Does anyone know for sure?
2seater
 
Posts: 106
Joined: Thu Sep 23, 2004 9:18 pm

Postby MikeyFIN » Fri Feb 04, 2005 8:23 am

[color=#000000]To gaz
That
MikeyFIN
 
Posts: 7
Joined: Thu Feb 03, 2005 9:20 am
Location: Finland


Return to Pitot Style Bench discussion

Who is online

Users browsing this forum: No registered users and 5 guests