Dual IM flow straighteners

[gnutz2]

Does anyone have any pictures of what flow straighteners look like on the inside of an dual plenum.

I'll be fabricating my own shortly and need something to copy

[turbofan]

http://jasperintegration.com/navi.html

[turbofan]

http://www.bufkinengineering.com/intake%20manifolds.htm

[newsh]

Good links!

[Rocco]

how big were the Audi S1 thorttle bodys?

[gnutz2]

Thanks, the second link is very intresting to read

But i have heard some of these dual plenum designs use flow straighteners to distribute the air even better.

Of course this would be difficult to see without cutting one open or if someone took pictures in the fabrication process.

[Rusty]

You're unlikely to manufacture something as complex as a dual plenum IM veery well without proper design and simulation beforehand. Will just be a big waste of time and money if it's not designed properly.

[gnutz2]

I'm going to build a flow bench to test the plenum designs before i fully weld it together, so it wont be blind

A simple flow bench can be rigged up with a fan and a few flow meters.

[andy10v]

derracuda on motorgeek made his own, more pictures in his project thread.

http://motorgeek.com/viewtopic.php?f=6&t=13390&start=1475

[quattro]

Whay kind of flow meters were you thinking of using?

[JP]

To even begin to properly simulate flow through an intake manifold on a flowbench you are going to need a tad more than a couple of fans. I struggle to get much more than a 10" pressure drop on a good flowing intake manifold running 8 x 1200watt vacuum motors.

As for achieving the correct sort of flow straighteners only way is to design it on a 3D simulator. Even then it is still not 100% as inreal life you can easily exceed the speed of sound through the transitions causing sonic boom shockwaves which will throw a big spanner in the works. Unless building a low boost setup or small turbo setup I personally would stick with the big taper plenumb concept. Lot easier to get even flow distribution for the novice so long the TB doesn't point directly at any given runner.

[gnutz2]

To even begin to properly simulate flow through an intake manifold on a flowbench you are going to need a tad more than a couple of fans. I struggle to get much more than a 10" pressure drop on a good flowing intake manifold running 8 x 1200watt vacuum motors.

As for achieving the correct sort of flow straighteners only way is to design it on a 3D simulator. Even then it is still not 100% as inreal life you can easily exceed the speed of sound through the transitions causing sonic boom shockwaves which will throw a big spanner in the works. Unless building a low boost setup or small turbo setup I personally would stick with the big taper plenumb concept. Lot easier to get even flow distribution for the novice so long the TB doesn't point directly at any given runner.

I'll only actually need one fan, we have lots of three phase industrial fans at work with motors up to and over 10kw and i wanted to run it on an inverter or just fit a damper because i think the fans we have may be too big. Also i was going blow the air into the TB and down the runners, not suck it through.
My problem is i dont have room for a large taperd plenum and therefore my TB does point at one runner in piticular.
All the dual plenums on the market are built for FMIC applications and i even doubt they would fit under the bonnet.

Whay kind of flow meters were you thinking of using?

To start with i was thinking of using the little ones you get to balance a car running ITB's but i think the best solution will be 5 manometers all coming back to the same board for easy reference.
Yes this would be measuring pressure not flow but i think it would work.
Failing that you could put a fan from each runner and measure the voltage, more voltage = more flow.
Or all the above, the more information the better.

derracuda on motorgeek made his own, more pictures in his project thread.

http://motorgeek.com/viewtopic.php?f=6&t=13390&start=1475

Thanks i was looking for that thread, i like the different approach he took.

[gnutz2]

Whay kind of flow meters were you thinking of using?

Something like this (correcly ducted) in the airflow of each runner would do the job.

http://www.extech.com/instruments/pr...tid=1&prodid=1

http://cgi.ebay.com/Digital-Thermo-A...item4aa8108190

Comparability is my only concern, so it wont be any concern if the CFM reading was terribly innacurate in the real world.

Also the sparky at work has some three phase inverters up to 5KW so i could have infinate control of air into the manifold which would be cool