Indepth study of WAI injection systems
I keep tellin ya, it's in the spring!!!!! That dang spring is causin pressure drop
I know you can't comprehend that, it's ok, you believe what you believe, I believe what I know.
dubbleugly01,
I am glad this is over, would like hear Mr Whoosh's view on the result of the test.
Flow drop by a check valve: irrefutable!
Pressure drop by a check valve: irrefutable!
I am glad this is over, would like hear Mr Whoosh's view on the result of the test.
Flow drop by a check valve: irrefutable!
Pressure drop by a check valve: irrefutable!
Not sure the video is entirely precise. Question: since the first test w/o cv has no way of stoping the line from emptying out in the end, how is this variable taken into account? From the end results I'm seeing a ~ 23% decrease in flow by adding 1 cv, and ~ 53% decrease by adding 2. This is hard to believe. The test needs to ensure that when the time is up the water is not allowed to drain from the tube into the beaker when there is no cv, b/c the cv will stop this flow when it is in place. While that may add to some skew, it is still undeniable that there is some drop in flow. ...but ~ 25% per cv?!? a bit hard to believe. lol sorry, I'm no fluid dynamicist either... just a lowly ME.
edit: I'd also really like the pressure drop test to be conducted with water. While regulation may not be as easy... it can't be much harder to just hook up pressure transducers/gauges before and after a cv with a real WI nozzle acting as the "adjustable flow regualator". Air is much more compressible than water and acts very differently. There was never a question of whether there is a dP across the cv, but in order to quantify it and rule out spring pressure, you have to actually use the medium that we are interested in.
edit: sorry for one last question, but what was the cracking pressure for the cv(s) used in the video test? Mine is 40psi, and I would like to know similar it is. Thanks.
edit: I'd also really like the pressure drop test to be conducted with water. While regulation may not be as easy... it can't be much harder to just hook up pressure transducers/gauges before and after a cv with a real WI nozzle acting as the "adjustable flow regualator". Air is much more compressible than water and acts very differently. There was never a question of whether there is a dP across the cv, but in order to quantify it and rule out spring pressure, you have to actually use the medium that we are interested in.
edit: sorry for one last question, but what was the cracking pressure for the cv(s) used in the video test? Mine is 40psi, and I would like to know similar it is. Thanks.
Last edited by honki24; Sep 6, 2007 at 05:45 AM.
The proper thing to do here is concede. Your test was well done and irrefutable. Please understand that at no time did I not state that there would be pressure drop and loss of flow across the valve. My error is in the psi drop caused by the spring across the valve.
dubbleugly01 please forgive my doubting your expertise.
Upon further pressing my Sr. Process Engineer, she stated that in practice, the pressure drops are added up across the entire system. In other words, if the spray nozzle will see 28psi in the I/C pipe, the nozzle needs 30psi to properly atomize, there are 5psi in line and fitting losses and the spring has a 8psi value...then the total system would require 71psi to see 30 psi downstream of the spray nozzle. She further stated that that will be a conservative, but safe, method to establish minimum pressure. "Better to error on the safe side she said". I thanked her and then later shot her for leading me astray.
dubbleugly01 please forgive my doubting your expertise.
Upon further pressing my Sr. Process Engineer, she stated that in practice, the pressure drops are added up across the entire system. In other words, if the spray nozzle will see 28psi in the I/C pipe, the nozzle needs 30psi to properly atomize, there are 5psi in line and fitting losses and the spring has a 8psi value...then the total system would require 71psi to see 30 psi downstream of the spray nozzle. She further stated that that will be a conservative, but safe, method to establish minimum pressure. "Better to error on the safe side she said". I thanked her and then later shot her for leading me astray.
Last edited by Whoosh; Sep 6, 2007 at 09:10 AM.
Whoosh, you are a gentleman.
I was in two minds about this, the urge to set up a test was so compelling to say the least!
I will continue on uttering the topic - please keep me honest - I was lucky this time.
I was in two minds about this, the urge to set up a test was so compelling to say the least!
I will continue on uttering the topic - please keep me honest - I was lucky this time.
Dribble after the system after powr off..
1. The no-CV video is timed for 1 minute. You can just catch a glimpse of scale reading at the moment the blue light bar turns off. Any dribble after that moment is added to the digital scale. I could not see that much increase in reading after the power off. (by the way, Abner did the video, I just read a bit further into the set up - he can confirm).
2. I will set it up with water one day, at present I just can't afford the time at present. 40psi check valve is very high, any reason?
1. The no-CV video is timed for 1 minute. You can just catch a glimpse of scale reading at the moment the blue light bar turns off. Any dribble after that moment is added to the digital scale. I could not see that much increase in reading after the power off. (by the way, Abner did the video, I just read a bit further into the set up - he can confirm).
2. I will set it up with water one day, at present I just can't afford the time at present. 40psi check valve is very high, any reason?
I picked it up from coolingmist when I built my first itteration of my WI kit. I've since switched to solenoids, but left the checkvalve in line. I am going to remove it when I get my car running again due to the testing found here. Good stuff. No idea each CV was affecting flow by nearly ~25%