Re-Silenced, pre-turbo...

[JHardwick]

Chillicothe, east on 35 from you.

 

[rbattelle]

JHardwick,



Please understand, in my comments earlier I meant no disrespect. Especially not to a fellow Ohioan.

 

[JHardwick]

None taken rbattelle, I can enter a debate and not take it personally …… even if I am wrong.



But, lol, I’m not sure that I am.



I don’t discount the formula.



But, I’m having a little difficulty believing that a mass of air can be pushed at a turbo face and pass through into the housing as efficiently as air sucked or directed to the center of the housing. Of course this could be similar to a river which flows quicker and more efficiently in the center than it does at the banks. Therefore, the flow would be directed toward the center of the housing anyway. Or does any of that matter anyway? Pushed or pulled with the passage efficiency being egual ... ... . will flow be the same?



Remember also that we are in fact talking about a vacuum, every time your filter minder is pulled down; you are seeing a vacuum.



I know your going to tell me that it doesn’t matter one way or the other, lol, as you can tell I am somewhat of a Layman.







BTW Duck,



I’m convinced that the EZ does lower EGT, the same way it gives me 2-3 MPG …… efficiency.

 

[rbattelle]

It's understandable that one might think that there is some fundamental difference between "pushed" air and "pulled" air. After all, when you're moving a couch, it makes a big difference whether you're pushing it or pulling it. I think there's a tendency to apply that sort of experience to things like air flow.



Think of it this way: both types of flow (flow caused by a turbo sucking and flow caused by a fan pushing) are actually both "push"-type flow. In the turbo example, atmospheric pressure is providing the "push" (because upstream pressure is lower), and in the case of the fan, the blades are boosting pressure and pushing the flow. Both examples produce flow because of a pressure gradient.



In the river example, you're talking about boundary layer. Flow at the banks of the river must be zero, and a parabolic velocity profile is set up which causes velocity to increase as we move toward the center, then decrease again as we pass center and head for the other bank.



And this is becoming a deep aerodynamics discussion, isn't it!

 

[JHardwick]

Originally posted by rbattelle

Think of it this way: both types of flow (flow caused by a turbo sucking and flow caused by a fan pushing) are actually both "push"-type flow. In the turbo example, atmospheric pressure is providing the "push" (because upstream pressure is lower), and in the case of the fan, the blades are boosting pressure and pushing the flow. Both examples produce flow because of a pressure gradient.



In the river example, you're talking about boundary layer. Flow at the banks of the river must be zero, and a parabolic velocity profile is set up which causes velocity to increase as we move toward the center, then decrease again as we pass center and head for the other bank.

A couple things and then I'll quit, lol.



If pushed vs pulled air were exactly the same, wouldn't a wind tunnel (a couple responses back) pull the air through as opposed to pushing it, effectively eliminating the need to straighten the air out?



I understand the boundary layer (again as a Layman) as the dead layer of air which will not hold atomized fuel in suspension pertaining to a gasoline engine. This is where turbulence is actually introduced with different surface textures to help maintain fuel suspension.



I'm done

 

[rbattelle]

There are lots of "suck-down" windtunnels. I worked on one for 2 years at NASA. But, there is still the need to "straighten the flow out", again because there's no difference between "pushed" and "pulled" air.



Ok, I think I'm done too!

 

[JHardwick]

LOL, I'm just a machinest ... ... ... ... ... can't speel it, but I are 1



Back to the original post, based solely on guage readings, the silencer has no effect on spooling or EGT IMO.



The EZ on 4 drops EGT's 50 to 100 degrees unloaded on my truck, but loaded and with 40psi of boost and the EZ on 4 I can hit 1300 easily if I am really crowding it.



I'm leaving mine out.

 

[Duck]

There will be a test on all of this later

 

[Blakers]

rbattelle,



Have you ever read my Uncle Eddy van Driest's studies in aerodynamics? One for instance: Charts adapted from Van Driest's turbulent flat-plate theory for determining values of turbulent aerodynamic friction and heat-transfer coefficients



These are from back when he worked for NACA and the Apollo program.



Blake

 

[rbattelle]

Blake,



Nope, had not heard of him until you mentioned it. Or maybe I have and forgot about it. Was he really your uncle?

 

[JHardwick]

Duck,



I'm sure that I am out of my league here.



I do geometry and other calculations on a daily basis, but this is WAY beyond my scope ... ... ... ... . my job is to question, thats how I learn. I was raised by a wonderful family who thought that engineers drove trains and the family farm would continue on.



I did for whatever reason branch the mechanical ability of the local farmer, combined with decent math skills, into a machine shop owned by a non-degreed owner ... ... ..... just ask the owner of Samson and see how I improved the 2. 5 ton military to fit the needs of these guys.



I may over engineer and lose long term sales, but at least they won't break ... ... ..... I also have parts for the 14 bolt rear and NP205 transfer, and as advertised any application where the stock casting won't cut it!

 

[JHardwick]

Oh, BTW, I'll be skipping the test, I think I feel a belly ache coming on that day!

 

[Blakers]

Originally posted by rbattelle

Was he really your uncle?

My great uncle. Here's just one of the things he wrote:



E. R. van Driest, "On the Turbulent Flow Near a Wall," Journal of the Aeronautical Sciences 23(11), 1007(1956).



WAY over my head!

 

[Ladders]

Can I be excused from da test??



Back to another "dumb" question (I havent asked it yet - sew its still dumb).



If we relate to the river but using the hoses, wont the ripples/bellows affect the flow on the edges and leave the center flow better? (try to explain this - huh huh huh?)



SOTSU!!

\\BF//

 

[rbattelle]

Certainly the "ripples" in the sides of the intake hose will "trip" the flow and make it turbulent there. In this case that might be good, since you might achieve a better flow rate (since the boundary layer - the region of slow moving air near the walls - is smaller). The question is, how much of that turbulence ends up entering the compressor? I don't have an answer for that.



JHardwick,

Being an engineer, you have my deepest respect as a machinist. In college I learned the machinist almost always has a better way of building a part than your design indicates!

 

[JHardwick]

Thank you rbattelle, I appreciate that.



Being a machinist since 11th grade and now owning a machine shop, I have worked with many, many engineers ... ... ... my hat is off to the engineering community as well!!!



I've also worked with young engineers from OSU, LOL. You almost always have to build a piece of junk to get them to see their errors, lol. And I got that "your just a machinist, I'm a college grad" look a lot too, hehe.



I've said a million times that these guys (gals) should have to spend a year on the floor before graduating ... ... preferably helping to produce their own designs. I think this would help them develope a better "vision".



The reason the machinist sometimes has a better mouse trap is because he has learned processes to make his job more efficient and it sometimes relates back to the original design.



P. S. I could tell you were an engineer, that's why I picked your brain a bit, it's how I'm getting my college degree, lol, a little at a time



P. S. S. Are you related to Battelle Institute in any way, or is this just a bit of irony.



Jeff

 

[Ladders]

Thanks for the "incite" (spell ckr - )



In electronics it is no different, you HAVE to build the circuit to prove it doesnt work. All degreed persons should spend some time with the "practical" side and it would enhance their experience. IF nothing else, the co would learn whom to "trust" and who not to (me thinks?).



SOTSU!!

\\BF//

 

[rbattelle]

I agree that many engineers (especially the young ones!) have no mechanical ability. What makes it particularly bad is the way they treat machinists. I watched many college students treat the machinsts like crap because "I'm an engineer and I know better than you". That attitude is total garbage. Our machinists used to just make the junk and then say "I told you so" when it didn't work.



As far as I know, I am related in some way to the people who founded Battelle. I've always wanted to go get a tour there, and maybe interview with them. Maybe some day.

 

[JHardwick]

I may be able to help you there Mr. Battelle



I have a friend who is a machinist there. He tipped me off on the fact that they are in the process of kicking off a contract in which they can only produce a third of in-house. My big customer was RCA until they started looking at China for small panels and Mexico for all others (including flat screen) that are currently produced here.



Anyway, I have my foot in the door as a supplier on this contract!



I'm pretty small, but I have CNC turning and milling, plus SolidWorks/CamWorks software to make programming more efficient (man I remember the days of paper tape and trig calculators, lol) ... ... ... ... I think these guys realize that I have the same technology with less overhead?



I'll keep you posted!

 

[JHardwick]

BTW Ben,



Out of curiousity, what does "SOTSU!!" mean, lol?

\\BF//





Well, I can't get the "\\BF//" under the "SOTSU!!", but you get my drift