Can an Anti-Lag Turbo Supercharger Increase Engine Efficiency and Performance?

[voltech444]

I've been thinking of an idea lately to increase the power to weight ratio of an internal combustion engine. It's from an already proven concept, anti-lag turbo. There's different types of anti-lag but the kind I'm referring to is sometimes called combustor can anti-lag. Basically a combustion canister with a fuel injector is added, with a bypass from the compressor going to this combustion chamber (which is part of the exhaust manifold) effectively turning a conventional turbocharger into a gas turbine engine. The turbo can be spun up to full rpm while the engine is at a low rpm; so boost is available the instant it's needed, zero lag.

Now I've been thinking of using this concept but in a little bit different way. Instead of just using it to spin the turbo up to speed, using it full time like a supercharger. In this setup there will be two turbochargers; one that is run like a regular turbo from the engines exhaust gases. The second one, is the gas turbine engine. The compressed air from the first turbo, goes into the compressor of the gas turbine engine, where it is further compressed. From there it goes through a Y-pipe, this Y-pipe goes to the diesel or gas engine, and to the combustion chamber. I don't believe a valve would be needed as the pressure differential should control the flow.

The compressor wheel on the gas turbine engine is larger than the turbine wheel, so all of the energy from the turbine wheel is used to spin the compressor wheel. Another option would be to have the gas turbine engine be the gas producer, and have another turbo (yes a third turbo) that uses those exhaust gases to spin a turbo and compress the intake air.

Basically it takes a lot of horsepower from the gas or diesel engine to spin a supercharger, of course there is a net gain in power from using a supercharger. With a setup like I'm describing it's like having a supercharger that powers itself. For a spark-ignited engine, water injection and an intercooler would be required to lower the charge temperature and prevent engine knock.

I know it's kinda a crazy idea, not sure if it would have a place outside of racing. I'm just wondering if this would be more or less efficient than just using a larger reciprocating engine to power a supercharger. Or maybe a turbo that goes into the supercharger to make even more boost?

 

[voltech444]

I haven't been able to findreceived any responses yet, I thought an idea like this would get people's gears turning; unless if somebody is writing a patent for the idea as we speak! any information anywhere discussing the setup I described above. It was an idea I've been thinking of for w while. I thought I would put it here as its a new and novel idea. I done know why I hav

 

[voltech444]

Well my phone chopped and screwed all that text up, ill have to fix it when I get home to my computer...

 

[rcgldr]

One alternative method (used by some race cars) is to cut fuel from the cylinders in a pattern that equalizes the heat between cylinders, and run more air through the engine. For example, even at a low throttle pedal position, like 20% or so, the engine throttle would be fully open, relying on the cut fuel to reduce power (at 100% throttle pedal position, no fuel would be cut). This would increase the exhaust flow from the engine at low rpm / low throttle settings. I don't know if this method would be more efficient than what is suggested in the original post. In the case of race cars, the engines are running at high rpm all the time, so most of the variation in a race car situtation is engine power output, with a limited range of somewhat high rpm.

 

[Vanadium 50]

Why a setup so complicated? Have a small turbo in line with a big turbo. The small one spins up quickly, and the large one more slowly. That smooths out the lag without sacrificing much fuel economy.

 

[voltech444]

I guess the point is that twin turbochargers put back pressure on the exhaust stroke which the engine does have to provide some energy to spin the turbos, not all of the energy but some of j. With a setup like I am talking about that extra work is being done by a separate energy source. The engine could always be running with full boost.

 

[Randy Beikmann]

voltech444, I have talked to some drag racers that spin up the turbo by injecting fuel and nitrous oxide into the exhaust system ahead of the turbo, and igniting it with a spark. Sounds wild, but effective!

 

[voltech444]

I also thought about injecting oxygen and fuel exactly like using nitrous, although it would also be necessary to inject water to keep the temperatures down and create more gas to drive the turbine.

 

[rcgldr]

voltech444, I have talked to some drag racers that spin up the turbo by injecting fuel and nitrous oxide into the exhaust system ahead of the turbo, and igniting it with a spark. Sounds wild, but effective!

If you do a web search for "youtube Larry Larson Nova" (the Nova is a twin turbo "street legal" drag racer that did 1/4 mile runs just under 7 seconds), you'll find a few videos of this method apparently being used, since in the night time videos, flames can be seen shooting out of exhaust pipes located at the front and rear of the car just before the car launches.

 

[HowlerMonkey]

I suggested this on another forum in 2009.

http://forums.hybridz.org/topic/76453-insane-wastegate-alternative/

It was patented in 1994.

It will probably show up in F1 next year if not already.

 

[rcgldr]

It will probably show up in F1 next year if not already.

F1 engines don't operate at low rpms, so the open manifold throttle combined with ecu cutting of fuel method keeps a high rate of exhaust flow at relatively low power settings. A few years ago, even when F1 cars were not turbo charged, this same method was used to increase exhaust flow since it was being used to assist the rear diffuser flow for increased downforce. F1 later changed the rules to not allow this, but it translates into quicker throttle response and/or it may help with the speed of the seamless shifts, so it continued to be used. Back to the current F1 cars, fuel consumption is an issue (100 kg initial fuel load and no refueling), and I don't think that using fuel to keep a turbo charger spinning is more efficient that open throttle with ecu managed fuel output.

 

[HowlerMonkey]

Dude...that's an electric motor in the center section of that turbocharger.

It doesn't matter whether it's on a long haul truck as Volvo uses it or on a formula one engine as Mercedes and a few others will use next year.

 

[rcgldr]

Dude...that's an electric motor in the center section of that turbocharger.

Is that how the KERS (kinetic energy recovery system) or at least part of KERS is implemented on F1 race cars these days (since they now have turbo chargers)?

 

[voltech444]

Is that how the KERS (kinetic energy recovery system) or at least part of KERS is implemented on F1 race cars these days (since they now have turbo chargers)?

I think the kers system uses electric regeneration using electric motors and batteries. Another system uses a carbon fiber flywheel that spins over 100k rpm if i remember correctly and then uses it just like regenrative braking. I think there's also pnuematic and even hydraulic versions they tried as well.

There are quite a few companies that are making electric turbos. When the gas engine is just running at a constant speed on the highway or something, the turbo is spinning the generator and storing it in a battery bank. When acceleration is needed the generator works as a motor and spins the compressor. Gives u better efficiency and maximum performance. Only issues is the motor/gen is very expensive because it needs to be designed to work up to 200k rpm, it also needs a complicated expensive inverter to convert the extremely high frequency and voltage down to a usable power. It takes a bit of energy to run the inverter, which lowers the overall efficiency. The only other option is gear reduction, which also uses energy, unless u used magnetic gears.

There's also companies making electric superchargers that use a Li ion battery pack and gears for centrifugal superchargers, or roots blowers. There are also a lot of scam companies that are selling electric superchargers that won't do dang for your car.