Benefit of a Vortex Generator in a turbocharged automotive applications

[bazzatron]

Benefit of a "Vortex Generator" in a turbocharged automotive applications

As the title states, What is, if any, benefit of creating a vortex in the air flow prior to it entering the turbocharger.

Here is a photo of the "Vortex Generator" in question.
http://forum.gtiroz.net/files/forsale9_713.jpg

Air goes into the opening in the middle of the photo, passes through the fins, and then travels through the rest of the pipe and out the other end where the blue connector(that is visible on the left) is connected to the vehicles turbocharger.

The claim is that a vortex of air is generated, spinning in the same direction as the fins on the turbocharger therefore causing less friction for the fins when they "grab" the air forcing it into the other side of the compressor. Therefore allowing the turbocharger to spool up faster than if there was no pre-existing vortex.

What I would like to know, is that would these fins create enough of a "vortex" to make a measurable gain in performance?

Does creating a "vortex" actually help the air pass through the fins easier? Or would it be like going up stream in a motor boat?

 

[Astronuc]

What I would like to know, is that would these fins create enough of a "vortex" to make a measurable gain in performance?

Probably not. But it's not possible to tell from a picture. It appears to a be static device(?).

Does creating a "vortex" actually help the air pass through the fins easier? Or would it be like going up stream in a motor boat?

The fins provide drag, and it's not clear their is a benefit. Also, consider the rpm of the turbocharger and how this compares with the airflow.

 

[pantaz]

Popular Mechanics tested several "fuel saving" devices, including two "vortex generators":

VORTEX GENERATORS
These devices, which are usually installed on the upstream side of the mass airflow (MAF) sensor, use stationary vanes or, on some devices, spinning blades to make the inlet air between the air cleaner and intake manifold whirl around in a mini-tornado. This vortex supposedly mixes fuel more thoroughly with air, which means the fuel will, theoretically, burn more completely in the combustion chamber. Trouble is, there's a lot of intake tract downstream from these devices designed to maximize a smooth airflow. Turbulence, coupled with the restricted airflow caused by the device, can only reduce the amount of air sucked into the manifold. Less air means less power.
Again, we tested two devices. The TornadoFuelSaver is a nicely made stainless steel contraption, available in an assortment of sizes to fit most vehicles. We installed it on our truck's intake tract immediately upstream of the MAF sensor. We purchased the second device, the Intake Twister, on eBay. It was crudely handmade from sheet-aluminum flashing and pop rivets. It looked like something we could make in about 10 minutes from an old soda can. The staff at UTI was reluctant to install it: The bent sheetmetal vanes looked as if they might break off and be digested by the engine. The device is one-size-fits-all, and is simply bent into a curl to insert it into the intake duct.


THE DYNO SAYS: Both devices reduced peak horsepower by more than 10 percent. The Intake Twister increased fuel consumption by about 20 percent; the TornadoFuelSaver provided no significant change.

http://www.popularmechanics.com/automotive/new_cars/1802932.html"

 

[B. Elliott]

These things have been in the automotive industry for about 10 or 12 years now. Any claims of increased performance or fuel mileage are flat out lies. As Astronuc stated, when you place the piece in the intake tract it's increasing drag ie; a restriction to incoming airflow.

An important part to note is how the 'vortex of air' does not continue to swirl after it leaves the part anyway. After the incoming air passes by the piece, it then passes by the throttle body, then enters the manifold plenum, then is separated and pulsed down into each intake runner as each valve opens. Any 'swirling' of the air before the throttle body, is lost at that point.

 

[leutious2]

One theory I came up with for this problem was simply changing from air to mist since you can get more air in the chamber that way. Next add a multi-wire fin behind a e-longated throttle and wa-la, you have minimized the plenum drag and increased air intake! problem solved. One more thing, keep in mind that you can only get so much BANG out of gas so don't feel to bad when you get to that limit some day.

 

[bazzatron]

I have seen and heard of these other fuel saver devices, but that isn't the purpose of this. This is down stream of the AFM (Air flow meter) and is said to help the turbo do its job easier. Air after the turbo and once its gone through an intercooler is going to lose any vortex in terms of mixing the air and the fuel better.

 

[paw]

I have seen and heard of these other fuel saver devices, but that isn't the purpose of this. This is down stream of the AFM (Air flow meter) and is said to help the turbo do its job easier. Air after the turbo and once its gone through an intercooler is going to lose any vortex in terms of mixing the air and the fuel better.

First of all a turbocharger is powered by the engines exhaust gasses, essentially waste heat, so small inefficiencies in the turbo have little impact on the overall performance.

Second, and perhaps more importantly, the turbocharger is designed to compress the air going into the engine by rotating it at some 20,000rpm. These vortex generators don't cause the air to rotate more than a few hundred rpm so they will make no detectable difference in the performance of the turbo and even less in the performance of the engine.

They are a scam, pure and simple.

 

[justme-]

For what it's worth- the concept of trying to spin the air in the intake to match the impeller of a turbo is wrong- you want to do the opposite. Proper turbo intake theory requires 24 inches of straight intake pipe ahead of the impeller to allow the incoming air to straighten before encountering the blades on the impeller. Bouncing, twisting, jumbled air in the intake will not be "bitten" well by the impeller and can even cavitate.
Gimmicks to increase mileage in cars have been around for decades (actually, as long as there have been cars!).

The only air intake item NOT disproven yet is the TAG (Turbo Air Guide) which is a honeycomb stainless steel grid installed in the intake immediately in front of the turbo housing to straighten the incoming air flow. Tests claim negligible air flow resistance up to considerable air flow requirements, and a decrease in boost for a given EGT in diesel engines meaning more air through the impeller and cylinders. I have not seen test results for gas engines to date.

Dodge trucks have a very similar item from the factory starting with the 05's.