Intake plenum and 911 throttle body

[jsceash]

The 997 T still has the same inherent issue with turbulence
Newton' laws of physics which apply to air as well as solid matter.
"An objects in motion stay in motion until acted on by an opposing force" The air entering the T will for the most part continue in the direction it is traveling towards the back of the T.
"Every action has an equal and opposite reaction" The air striking the back of the T will rebound into the air stream causing turbulence.

Bens design Pedro Techno Torque 1 and 2 and IPD are better solutions. The incoming air hits the flat back of the stock T and compresses before it move sideways causing not one but three turbulent areas one in the back high pressure and on the top where to low pressure accumulate at the radius to the inlet to the two exits. There are Cad test drawings showing how ineffective this is in one of these threads.
Pedro system the cheapest alternative. adds a deflector V in the back creating an actual flow Y. IPD all aluminum design is molded with the same V diverter Bens is a copy of IPDs design, which I doubt he will be allowed to sell due to patents from IPD. In the end there is about a 25% improvement in this design you can't get from the stock distribution T.

Look at the video from about 7 minutes in
https://www.youtube.com/watch?v=B-fXau-xWO8

The negative on IDP is the $795 price opposed to Pedro's or Ben's design. note the IPDs design is the same and it totally coated in epoxy inside.
https://www.youtube.com/watch?v=SneTb8-cHbo

I doubt anyone who has one of these designed systems would ever go back to the factory Distribution T.

[KRAM36]

Originally Posted by jsceash

The 997 T still has the same inherent issue with turbulence
Newton' laws of physics which apply to air as well as solid matter.
"An objects in motion stay in motion until acted on by an opposing force" The air entering the T will for the most part continue in the direction it is traveling towards the back of the T.
"Every action has an equal and opposite reaction" The air striking the back of the T will rebound into the air stream causing turbulence.

Bens design Pedro Techno Torque 1 and 2 and IPD are better solutions. The incoming air hits the flat back of the stock T and compresses before it move sideways causing not one but three turbulent areas one in the back high pressure and on the top where to low pressure accumulate at the radius to the inlet to the two exits. There are Cad test drawings showing how ineffective this is in one of these threads.
Pedro system the cheapest alternative. adds a deflector V in the back creating an actual flow Y. IPD all aluminum design is molded with the same V diverter Bens is a copy of IPDs design, which I doubt he will be allowed to sell due to patents from IPD. In the end there is about a 25% improvement in this design you can't get from the stock distribution T.

Look at the video from about 7 minutes in
https://www.youtube.com/watch?v=B-fXau-xWO8

The negative on IDP is the $795 price opposed to Pedro's or Ben's design. note the IPDs design is the same and it totally coated in epoxy inside.
https://www.youtube.com/watch?v=SneTb8-cHbo

I doubt anyone who has one of these designed systems would ever go back to the factory Distribution T.

Our engines don't work like that. Our engines pull air into it, that's the force acting upon the direction and travel path of the air. Pedro blows air into the Distribution T, which will hit the back of the Distribution T and the wedge would have a nice impact on the way the air travels. Our engines pull air in and it rides along the side of the Distribution T. That's why the Y shape is very important and having the wedge is not.

Originally Posted by blue2000s

I'm using Fluent in these simulations.

A Y will be more efficient than a T for airflow in a steady state, that's correct.

Keep in mind that with three cylinders to a plenum, there is a pretty much constant flow of air into the plenum when the engine is kept at a constant speed. There is always a cylinder pulling air. The pulses that influence secondary pressure waves are important, but they are secondary in nature so the influence on flow is on a much lower order than the primary vacuum pulled by the cylinders themselves.

Here are three more simulations varying on the one I posted earlier. The first one just adds a sloped wedge to the original T. The second adds a large radius to the T junction and the last one combines the radius with the wedge.





The volume flow rate results show that the T and T with wedge have almost identical flow rates. The radius-ed T with and without the wedge are both almost the same flow rates but are about 30% greater than the standard T.

http://986forum.com/forums/general-discussions/31693-maf-throttle-body-diameter-2.html

[KRAM36]

Originally Posted by KRAM36

Our engines don't work like that. Our engines pull air into it, that's the force acting upon the direction and travel path of the air. Pedro blows air into the Distribution T, which will hit the back of the Distribution T and the wedge would have a nice impact on the way the air travels. Our engines pull air in and it rides along the side of the Distribution T. That's why the Y shape is very important and having the wedge is not.

Holy Mother of God! I was chastised over this post and 1 1/2 years later the great Jake Raby says the same thing I did about the air being pulled along the short side radius. The Y shape is the most important part of the piece, even according to Jake Raby.

Originally Posted by Originally Posted by Flat6 Innovations

No, it doesn't.

The short side radius of the IPD is where the trick is. You can't develop an intake component using a shop vac. If you do, you'll never see that what you are doing is hurting performance, or doing absolutely nothing!

With a pitot tube inserted in the intake where the splitter is installed in this photo will give zero, or very, very little velocity on the flow bench. Why? Because the air is pulled to the short side radius.

Yes, I have direct experience with this.

https://rennlist.com/forums/996-forum/944002-alternative-to-ipd-plenum-2.html#post13767949

[blue2000s]

Originally Posted by jsceash

The 997 T still has the same inherent issue with turbulence
Newton' laws of physics which apply to air as well as solid matter.
"An objects in motion stay in motion until acted on by an opposing force" The air entering the T will for the most part continue in the direction it is traveling towards the back of the T.
"Every action has an equal and opposite reaction" The air striking the back of the T will rebound into the air stream causing turbulence.

Bens design Pedro Techno Torque 1 and 2 and IPD are better solutions. The incoming air hits the flat back of the stock T and compresses before it move sideways causing not one but three turbulent areas one in the back high pressure and on the top where to low pressure accumulate at the radius to the inlet to the two exits. There are Cad test drawings showing how ineffective this is in one of these threads.
Pedro system the cheapest alternative. adds a deflector V in the back creating an actual flow Y. IPD all aluminum design is molded with the same V diverter Bens is a copy of IPDs design, which I doubt he will be allowed to sell due to patents from IPD. In the end there is about a 25% improvement in this design you can't get from the stock distribution T.

Look at the video from about 7 minutes in
https://www.youtube.com/watch?v=B-fXau-xWO8

The negative on IDP is the $795 price opposed to Pedro's or Ben's design. note the IPDs design is the same and it totally coated in epoxy inside.
https://www.youtube.com/watch?v=SneTb8-cHbo

I doubt anyone who has one of these designed systems would ever go back to the factory Distribution T.

This is going to be technical. Sorry, it has to be. The answer is recirculation. The slow moving air that naturally forms the wedge forms a high pressure zone that diverts the incoming flow. As Newton or more precisely Navier-Stokes would tell us is that the path of a fluid particle is influenced by the forces on that particle. The high pressure of the stagnated wedge diverts the streamline of air away from the back of the "T". So the air coming in from the throttle body never "bounces" off the wall. The effect of a physical wedge is more likely to disrupt the secondary pulsation supercharging effect of the tuned plenum than it is to help bulk flow in any way. A simple flow bench test will prove this out.

I know people like to refer to detached flow as "turbulence", but it's really not accurate (It's one of those things that annoys a fluids engineer). In reality, most flow through the engine is turbulent, which means that the air particles within the freestream is not generally taking a linear path. There is more energy in a turbulent flow, which helps keep the freestream attached to a surface. This is why they make airflow turbulent at the leading edges of airplane wings with little triangles and golf balls have dimples.