00cls1camaross

iTrader: (10)

So we are in the process of designing a ram air system for my car, I have read the threads about Ram Air I and II. Basically my understanding is all a single outlet ram air will do it raise volumetric efficiency because it brings the pressure for the ram air/intake closer to atmospheric pressure.

What we decided on the system we are going to build, is that the two slots pictured here:

If we make it sealed with the two slots going up toward the mass air flow sensor, and then merging into my mass air flow sensor could some pressure be created, because it is a converging ram air, it will shrink from the size of the grill holes, and then shrink into one 78 mm MAF sensor.

Has anyone actually checked pressure of their Ram Air, before and after an amount of speed like 75+? I was thinking of seeing if i could get my hands on some tools to test this.

This will be a completely sealed system, i don't drive in rain, i live in PHX, AZ. Some actual thoughts and opinions and data would be nice, thanks for reading

00cls1camaross

iTrader: (10)

ideas ideas?

treyZ28

it's really hard to compress air via energy from velocity drop at car speeds.

00cls1camaross

iTrader: (10)

yeah i read air was not able to be compressed until .5 mach on this site but i don't know how true that is. if two pipes of air are filled with air and then merged with one, i cant imagine the pipes just stopping and waiting for the merge into 1 pipe to be filled and continue on slowly. In my mind it seems like there would have to be some sort of compression of the 2 airs into 1, as minimal as it is.

treyZ28

I think you're confusing that with the term "compressible flow"

All you are doing is taking energy and transferring it. Think of it as a giant rock pushed off a high cliff and weight landing on a spring and compressing it. Potential energy transfered to kinetic and then into the spring (potential).

It's the same thing. Kinetic energy of air transfered into pressure. Even at 1mph, air is compressible. It's just energy. It's not really considered to be significant till about M=.5

gametech

iTrader: (1)

The funnel effect that your picture seems to show would increase velocity, not pressure. I'm sure the Japanese sportbike manufacturers who have millions in development dollars and few (until recently) emissions or noise concerns have good reason not to use a "funnel" style ram-air setup on any of the sportbike intakes. This is one of those instances where physics is highly counter-intuitive. The whole concept of pressure and velocity being inversely related rears its ugly head.

00cls1camaross

iTrader: (10)

i had a aerospace engineering teacher calculate the pressure change at 120 miles per hour using Bernoulli's equation. The ending velocity is 0 regardless if it speeds up in the converging pipe. Velocity is increased but when it hits something the speed is 0. With that increased air movement we calculated .25 psi at 0 velocity. Im still trying to figure this out since i am going to school for physical therapy and not physics haha.