Audi V6 3.0 TFSI: First ever compressor engine in Audi history!

[EnI]

I've found this on Fourtitude forum ...



CLUTCHED SUPER TURBO CONTROL STRATEGY


Abstract:

A method of controlling an internal combustion engine boosting system of the type including an exhaust-driven turbocharger (33) and a mechanically- driven supercharger (15). The supercharger (15) includes rotors (21) and a clutch (27) operable in a first condition (FIG. 1) to transmit torque from a mechanical drive source (E) to a supercharger input (25) in response to a positive input (75), and operable in a second condition (FlG. 2) to interrupt the transmission of torque from the source (E) to the input (25). The method is characterized by determining possible operation of the clutch (27) in a first condition (FIG. 1); and commanding a bypass valve (53) toward a closed position (FIG. 1), forcing air through the supercharger (15). The airflow causes the supercharger rotors (21) to rotate, thus rotating the input (25) of the supercharger prior to the clutch (27) operating in the first condition (FIG. 1).

Detailed description of the system: http://www.wipo.int/pctdb/en/wadLis...7/2008&TYPE=A1&DOC_TYPE=PAMPH&PAGE=0&ACCESS=D


Martin, any new comments after reading these tech details?

 

[Family Guy]

What I don't understand is why is Audi calling it TFSI and not CFSI or KFSI?

Or SFSI since VW called there Turbo-supercharged engine TSI

 

[Sunny]

Both supercharging and turbocharging have their pros and cons.

Agree, but efficiency is not one of the pros of supercharged engines. But hopefully Audi has some ace up there sleeve.

 

[coolraoul]

It is a little surprising that I see quite a bit of "negative" impressions about this new supercharged engine from Audi. Both supercharging and turbocharging have their pros and cons. Just because BMW happens to make a VERY good twin turbo setup doesn't mean that supercharging is a bad idea.

Merc and AMG have had supercharged engines for a long time (from the 1.8L Kompressor in their small cars to 5.4L Kompressor in the 55 AMG cars). These cars made decent power, had a flat broad torque curve, and were pretty fuel efficient compared to the competitors. They've pretty much "been there, done that" with supercharging, so they are likely moving towards turbos. Audi, on the other hand, has always championed turbo technology.......they've "been there, done that", and now are trying an alternative in supercharging. Nothing wrong with that, as I'm sure the supercharging technology is always continually improving (like turbo technology). BMW (prior to the 335i) has championed a naturally aspirated approach for the LONGEST time. Now they are into turbocharging their smaller engines to make the same power as bigger naturally aspirated engines.

There is a natural tendency to "change" to seem keep up with the times. Bottom line, everyone recognizes the need to go "green" to a degree, and forced induction (with either supercharing or turbocharging) is the way to go while still making decent power.

I don't think it is that simple. You can't move to a tech just because you want to change. So maybe, Audi will then move to N/A diesels, because they did turbocharged diesels for a long time? No, because a diesel needs a turbocharger.

If a Kompressor has inherent disadvantages (needs power to work, not very fuel-efficient) over a turbocharger, Audi wouldn't build one only because they're bored by turbochargers and the engineers wanted some changes, would they?

But they're not stupid either. So this motor must have some advantage over a turbocharged one. Maybe Audi is bored by turbochargers dying all the time and wanted some reliability? Maybe they found a way to improve the tech, just like BMW did with the 35d and 35i?

Rememeber VAG is exploring new ways, like the turbo and compressor petrol engine TFSI, they may discovered a way to make supercharger better than turbocharger. But they certainly did not build it because of boredom towards turbo tech!

 

[EnI]

According to Eaton's patent the new engine is " an advanced TSFSI" - "an advanced superturbo with direct injection" : using direct injection, supercharger, and turbocharger.

So instead of a sequential-twin-turbo or relatively small twin-turbo, Audi opted for a sequential supercharger-turbocharger combination to gain the same results while preserving compact dimensions of the (lighter?) engine.

Supercharger-turbocharger combination in similar to the TSI engines by VW. Although in Audi engine the direct injection is included (or is it also present in TSI as well?).

But the real innovation it seems to be the new method of controlling the boosting system / process by adding bypass valves & improved supercharger clutch operation.

 

[martinbo]

Hey EnI... how you doin' mate?

Um, I'm not certain as to why you're referring to the sequential "Twincharger" technology employed by VWAG wherein both a supercharger (to generate low-rpm boost) and a turbocharger (providing boost at higher rpm - thereby elimating lag) are used in conjuction for forced induction. Engines such as these are referred to as TSI engines. TFSI is for "Turbo Fuel Stratified direct Injection" as up until now was used to specifically denote turbocharging-only engines.

This new Audi engine is supercharged only; in my opinion Twincharging is mechanically and economically exempt from being applied to engines of a V configuration because of complexities involving the plumbing needed for both 'chargers.