Intake Manifold Design

Depending on your A2W setup, another radiator just for the A2W can get temps down to ambient pretty easy.
 
NyCowboy87 said:
Great info guys, I have leared a ton just sitting back and reading what you all have to say.

I was always under the impression a2w coolers were more efficient, problem being that the air could only be cooled to what engine coolant temp was. Unless you have a drag/pulling rig and run an ice box with chilled water or some other sorts of cooling the fluid (seperate radiator) it makes an a2a more desireable on the street. With an a2a temps can be seen within 10-15* of ambient temp given you have enough air moving across the cooler surface and/or depending on cooler size and charge temp.
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After some reading last night, water has far better heat transfer qualities over 50/50 water-coolant mix and straight air apparently. If the A2W were to be absolute design on anyone's intake, would you use one material throughout the design or incorporate a dfferent material. The Effectiveness is the apparent standard nomenclature for raing them.

How cold can we go before power drops off if it even drops off with all the finning and cool-cans? Found this link thought I would post it.
http://www.hotrodhotline.com/md/html/aluminum_vs_copper.php

If we were to incorporate a water cooled manifold, how would we develop the internal to not interfere with flow unless a coolant tube can be placed in an area that will not effect with other smaller probes of some shape which could even be used to steer a laminar state of flow into the runners.

Aftercoolers equation from Charles F. Taylor pg 392 in Volume 1

Cc = T1-T2 / T1 - Tw
T1 = entrance stagnation temperature
T2 = exit stagnation temperature
Tw = coolant entrance temperature
Cc = the cooler effectiveness

Things I have thought of as far as plenum and runners. The shape itself of the plenum has be thought to have an influence on certain wave cancellation, how true that is a person studying acoustics could tell that or a seasoned engine builder/tuner. Gale banks has a few manifolds utilizing round cylindrical plenums, could they be dominate over square or will vice versa be present hand in hand.

Are we including runner volume in addition to plenum volume (dictated by tuned length & air speed desired), because I believe we should. Now thee is something along the lines of runner volume to cylnder volume ratio to think about. I know Greg says we should just disregard velocity (ie however anyone believes lets use his point as an example) with forced induction, we should make this point that we still need a certain air speed to adequately fill our cylinder and one point with that is our control is indeed the convergent and divergent sides of the valves in the cylinder head & the valve itself.

So if we just shove air into the cylinder whats the advantage over tuning with waves? Simplicity or is there really the wicked tune that will Since we have higher pressure, our waves themselves react quicker among runner ends because high pressure waves travel faster than lower pressure waves within the system and have a different reflection nature the more and more I study.

So we don't ge things mixed up as far as waves directional or density, Positve wave = towards cylinder, Negative wave = away from cylinder. Do not get mixed with positive pressure waves and negative pressure waves.
 
9724VF350 said:
Depending on your A2W setup, another radiator just for the A2W can get temps down to ambient pretty easy.
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Has anyone ever cared to check the exit temp of coolant at the engine radiator? It may be closer to ambient than you would think.
 
Ghostman said:
Has anyone ever cared to check the exit temp of coolant at the engine radiator? It may be closer to ambient than you would think.
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Other than grabbing the lower hose by hand? :hehe: No. But now that I think of it, yes it can be pretty close to ambient at times.

I was thinking that with pickup cooling systems and much power while towing, ect, most struggle to keep things cool. At this point outlet temp is going to be it's highest, at the same time you want your intercooler to be most effective.
 
Fahlin Racing said:
Are we including runner volume in addition to plenum volume (dictated by tuned length & air speed desired), because I believe we should.
So if we just shove air into the cylinder whats the advantage over tuning with waves? Simplicity or is there really the wicked tune that will Since we have higher pressure, our waves themselves react quicker among runner ends because high pressure waves travel faster than lower pressure waves within the system and have a different reflection nature the more and more I study.
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Yes, the volume of the remaining runners should be included as part of total plenum volume.

Waves in a system exist independently of air flow and are caused by the rapid pressure pulses caused by the valves opening and closing, so regardless of how we get air into the cylinders, the waves are still there. Charge air crashes into the valve and a compression wave bounces back and up the runner, just as air does in an NA application.

A waves velocity is not related to pressure, so higher pressure waves do not travel faster than lower pressure waves. The velocity changes with respect to temperature.
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The primary advantages of an a2w IC over an a2a are it's effectiveness per size, it's ability to cool charge air to less than ambient temps, and that it can be mounted anywhere. Primary disadvantages are system cost, weight, and eventual heat soak (without proper heat exchangers).

I have never installed, seen, nor even heard of an a2w system that was plumbed into the engine coolant. I'm not saying it hasn't been tried, I just have never seen or thought about it. They always have their own water reservoir and pump as well as small heat exchanger(s) with proper ducting and electric fans. If anyone has pics of the former setup then that's fine I guess, but that just sounds like a terrible idea, and here's why:

Ethylene Glycol does not have near as high a specific heat as compared to water. Almost nothing does.
Using the engine coolant system will drastically reduce the effectiveness of both heat exchangers. Coolant temp being low when we are idling or in ANY situation that allows us to reach in and grab the lower hose is a situation where none of the components are even in any real use. Personally I would hesitate to use that as an accurate operating temperature to base the design of an IC system off of.
We not only further stress the cooling system by adding an additional high heat input into the system, but are now pumping hotter water through the IC, further reducing effectiveness.
 
Child 9 - lots of bus and gen set VE and P-pumped motors had engine coolant cooled aftercoolers that bolted directly to the intake
there are more tha na few new and used for sale on Ebay as we speak
 
Alright! And that example is tapped into the engine cooling system? It does have good compact packaging. If that was made out of aluminum it could be almost ideal, but regardless if that was plumbed to a separate water tank and heat exchanger that would be a nice solution for intercooling a DD/street application. If I had a Cummins, I'd have that. With cold water that is a guaranteed significant power adder.
 
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I know I keep asking this - and some of you keep plugging away at the theory etc - but once again - I will say it is all meaningless unless you can try putting it in real terms

like i suggested - pick a motor - pick a cam, pick an rpm, and design an intake

tellin us that the wave isnt gonna do anythign productive unless it hits the valve at precisely the right time is meaningless in the real world

given that a poor intake and an engineered to the 11th degree intake is likely only about 5hp apart at most rpms except for the one rpm range the engineered intake was designed for - it is a moot point for the most part

but then I have iterated that several times as well. And yes Fallin - I know what forum this is

Instead of spouting theory and specualtion that can be read anywhere on the net - pick a popular motor like the 5.9 , use your theories and speculations and figure out length of runner, diameter, angle of runners past the obstructions, plenum shape and size

With all of the formulas readily available on the net all you need is a calculator for most of this, and some time :)

maybe it is/will be calculated to be a tapered plenum, of X size, with dual inlets, with a reveerse taper oval runner that is some 17" long to provide a venturi effect, and a couple reversion steps located in appropriate locations, etc etc etc etc

It wont matter if it doesnt work - but what it will do is put a fresh face, and a pictorial of what one might look for or design, that isnt here today like all the run of the mill short runner log plenum intakes one can buy on the market today
 
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child9 said:
Alright! And that example is tapped into the engine cooling system? It does have good compact packaging. If that was made out of aluminum it could be almost ideal, but regardless if that was plumbed to a separate water tank and heat exchanger that would be a nice solution for intercooling a DD/street application. If I had a Cummins, I'd have that. With cold water that is a guaranteed significant power adder.
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Its the top part of the intake shelf on most of them. All the 4bt bread truck engines I've seen are set up that way.

Sent from my DROID RAZR HD using Xparent BlueTapatalk 2
 
IMHO it is fruitless to attempt to design anything without first acquiring a trully in-depth understanding the physics involved. You keep essentially asking someone to build you an aircraft without understanding the nuances and details that affect lift. You might end up with a chair with a corkscrew on top.

You said "it won't matter if it won't work"...and that my friend, is crazy talk. The very concept of setting out on a project that is not designed to work almost made my head pop.

I'd CAD up something crazy for you as a joke, but I'd hate for someone to mistake a CAD file posted as me being serious. :/
 
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Child9 - there isnt a single invention of our time where someone KNEW all the physics and nuances involved.
Especially airplanes lol - the Wright brothers flew by the seat of thier pants more than a few times before it worked
the physics of intakes is already out there - and so are the formulas - one doesnt need to KNOW in order to apply them - APPLYING them and failing a few times is the learning part of the knowing. Understanding why it failed is learning. And yo udont think for a second those formulas came from thin air - they came from trial and error and the errors were explained from the science which drove them to try again
Not a one of you will ever get there if you think you need to mentally rewrite everyhting
The only way you get a new box is to step outside the old one
So draw away using some modicum of skill rather than fecitiousness (spelling)
if it looks like a chair but works - who cares
 
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I do. I care. I care about the work of the giants that came before us. The Wright brothers were scientists, not just bicycle makers. They were highly educated. They built a lot of innovative devices and they spent years studying wing design...like one of the first wind tunnels. I care about effectiveness, aesthetics, and limiting waste. I consider something not only working well but looking good doing it as the mark of a professional, and as such that's what I strive for. If you don't that's cool. No one is telling you what you need to do. Just stop telling those who care to discuss the in depth theory of compressible fluid dynamics that we need to stop talking and start building. The assembly is the easy part. Good solid design is the challenge. Fluid dynamics is a real weird field, and while it's true we have some formulas that can help quantify some basic fundamental principles, we by no means have it all figured out. I feel that discussing the ideas above is completely expected in a thread called "Intake Manifold Design" in the "Competition Vehicle Build-Extreme Engine Tech" sub-forum.

Sorry for coming off facetious earlier, that was not my intent.
 
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So, using physics and math, can anyone tell me what RPM I had in mind when I designed this manifold for my 363ci Cummins? I can send you any dimension you need in your calculation.

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A big open plenum I cant understand how the air could even find its way to the valve.
 
Do we get to ask several yes/no questions? :) What was that game show? I've Got A Secret?

1.) Is the total manifold volume (manifold plenum + 5 runners) approximately 545 in^3?
 
Technically the port lengths plus the flange thickness are the runners in that case...so they are around 5" long. :)
 
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