I know KERS is now a dead issue, but I was curious. Does anyone know if KERS really saved gas, considering the way the drivers used it? I would believe that it would give better gas mileage if the drivers were, say, on a straight section of track, and they pressed the KERS button while maintaining the same speed. But every time I saw it being used was for increased acceleration, like a turbocharger. When used in this way, with the engine already on maximum acceleration, it seems there wouldn't be any gas savings. If this is the case, KERS wasn't green or environmental. I wasn't against KERS and it added an interesting element to F1 racing, but it seemed requiring it so that it would be good for the environment when it may not have been would have been an unnecessary cost.

There are two ways of looking at KERS. One is as a "green" technology that saved fuel and/or reduced pollution by recapturing some of the energy wasted under braking. That, the Formula One system did not do.

The other is to see it as an aid to accelleration, the way the "serial hybrid" systems in Honda's Insights and various GM and Ford products use it. There, as you say, it served as "an electrical turbocharger," adding about 10% to the car's power for a short time -- about six seconds a lap. In this, the KERS system was successful, if you accept what the SPEED commentators said.

10% more power for six seconds may not sound like much, at first glance, but it has its effect. A driver can use it to fend off an attack if he's leading or make a pass if he's doing the attacking. Either way, he's getting back a small fraction of the energy the car uses each lap.

The Formula One KERS system is not exactly "green" in this application, but it does show that a system like like it is practicable. Developed further, and with bigger batteries and motor-generators, it could help small displacement engines deliver good fuel mileagem yet still have decent accelleration when needed. And nothing beats the daylights out of a part or system faster than racing. In that respect, it may be worth the money, after all.

Besides, it does add another element to the high-tech, high speed chess game that is Formula One.

I'm surprised none of the teams have used turbo-compounding. Does anyone know if they have in the past? I know turbocharging is banned, but I am not aware of any rule that bans turbo-compounding. Of course, it may not work well on a naturally aspirated engine. I've only seen it on turbocharged and supercharged engines.

Cat-Man-Do - 20 November 2009 07:48 AM

I'm surprised none of the teams have used turbo-compounding. Does anyone know if they have in the past? I know turbocharging is banned, but I am not aware of any rule that bans turbo-compounding. Of course, it may not work well on a naturally aspirated engine. I've only seen it on turbocharged and supercharged engines.

For those of you who are wondering, "turbocompounding" involves putting an engine driven or electrically driven turbine in the exhaust system. Think of it as the opposite of a supercharger -- instead of forcing air into the cylinders, it sucks it out of the exhaust manifold. This reduces exhaust back pressure and thus frees up some of the power lost to "pumping losses" of the pistons forcing exhaust gasses out of the engine and through the exhaust system.



Turbocompound Diagram ↑

Engines With Turbocompound System ↓





It is quite possible that someone has thought of turbocompounding an engine (I concieved the idea -- using a roots-type supercharger -- when I was in the 8th grade) but the Formula One rules simply don't allow it. Other considerations: The exhaust systems on Formula one cars are very short and the turbocompound system is large, heavy and requires considerable maintenance work. Thus, assuming it wasn't illegal, turbocompounding may not be worth the effort.

^Some interesting photos. Haven't seen them before. You have the operating principle wrong though. The purpose is not to suck the exhaust out but to recover power lost in the exhaust stream. It would increase back pressure in a naturally aspirated engine, which I suspect is one reason F1 doesn't use it. With a turbocharger the exhaust power that spins it is absorbed by the compressor wheel that compresses the intake air. With turbo-compounding the recovery turbine is downstream of the turbocharger and the recovered power is fed back into the accessory gear drive instead of to a compressor wheel. One of the most successful such applications was in the Wright R3350 radial engine that powered a number of aircraft, most notably the DC7C. Current Detroit Diesel engines recover around 50 hp using the system, which, by the way, is quite compact and nearly maintenace free. Good thinking for the 8th grade, but a Roots blower won't work for this type of application. Probably the most bizarre turbo-compound ever built was the Napier Nomad aircraft engine. A commercial failure, but what a magnificent monstrosity!

Thanks for the correction, Cat-Man-Do. I found another source on the subject who said the same thing you did, almost word for word. I suppose it's possible that a turbocompounded engine would be low-maintenance, but that's for aircraft, where things have to work, first time, every time. No telling what the Formula One crowd would do with them. All in all, from the outside, the turbocompounding mechanism looks somewhat like the current KERS system except that it uses exhaust gas to turn the crank, rather than electricity.

As for that thing in thought up in 8th grade study hall, my objective was to use a pump or blower of some sort to suck exhaust gas out of the engine. I had no idea it might actually drive the engine. I wonder what would have happened if something like that had actually been built.

I also found some pictures of the Napier Nomad. That was a two-cycle diesel engine for aircraft use.



Rube Goldberg would have loved that thing. It used just about every trick in the book from turbocompounding to supercharging to an exhaust jet with an afterburner. The engine itself is in the picture above, the one below is a diagram of the engine, all its bits and widgets and how they all worked.

Napier Nomad engine diagram. The information below comes from the [url]http://home.xmsnet.nl/hdejong/Nomad.html[url] web site.



1: The piston engine itself: a 12-cylinder, 41-litre, opposed-piston two-stroke diesel.

2: This propeller is driven by the crankshaft.

3: Yes, there is an afterburner in the exhaust.

4. The exhaust gases drive an axial multistage turbine. With the valve [4], half the turbine can be closed off.

5. The turbine drives an axial multistage compressor.

6. The turbine also drives the second propeller.

7. The hot air from the supercharger is led through an intercooler.

8. And then through a radial supercharger that is powered by the crankshaft.

9. The thrust from the exhaust gases is also made useful.

The afterburner and intercooler have shunt ducting, so the engine can be run in a number of modes depending on power requirements.

The result is a very fuel-efficient engine (163 g/bhp/hr) that produced 3000 bhp plus 1.4 kN of thrust. It was rather hard to get it to run well, so it never progressed beyond the prototype stage. Applications: (UK) Avro Lincoln (testbed), Shackleton (proposed); Blackburn and General Beverley (proposed).

A simplified version was also tried: the Nomad 2, with a single propeller, without the supercharger, and with the turbocharger linked to the crankshaft instead of the second propeller. The Nomad 2 (or "E 145") didn't see production either. Applications: (UK) Airspeed Ambassador freighter (proposed); Avro Shackleton (proposed); Blackburn and General Beverley (proposed).

^You should check out "sleeve valve" engines such as Bristol's and Pratt and Whitney's monster H-3130 (H pattern layout, 24 cyl, sleeve valve). Then there are always the rotaries like the Le Rhone and Gnome. The designs and concepts tried in the past make most of today's stuff look pretty bland.

Cat-Man-Do - 21 November 2009 12:42 PM

^You should check out "sleeve valve" engines such as Bristol's and Pratt and Whitney's monster H-3130 (H pattern layout, 24 cyl, sleeve valve). Then there are always the rotaries like the Le Rhone and Gnome. The designs and concepts tried in the past make most of today's stuff look pretty bland.

I saw some of those. The closest I've seen in race cars was BRM's "H-16," raced in 1966. I knew of the LeRhone radial (crank shaft stayed put, whole rest of the engine rotated around it) and sleeve valve engines. I understand Michael Hewland (of Hewland racing transmissions fame) experimented with a sleeve valve engine twenty-some years ago. No idea what came of that project, if anything.

However, if you want to see what may be the all-time "Captain Weird" of piston engines, check this out:



It's a "Delta" engine; a form of opposed-piston engine. (see below)




Opposed Piston Engine
With Vane-Type Supercharger


It has six pistons, three crankshafts, it has sleeve valves and no cylinder heads. The pistons comming together, head-to-head, are the combustion chamber. Imagine trying to rebuild one of those and stuff it in your Vespa. Then imagine the problem of trying to build one transmission to run all three cranks to one rear wheel.

In case you're curious, the engine in the gif file has a sliding-vane type supercharger, which is tha big, eccentric thing inside what looks like a turbocharger case at the upper left.

I'm sure there are weirder engines out there, but you'd have to look for them. Speaking of which... this "Infobunker" web site, http://www.petealbrecht.com/blog/blogapril2006.htm , has some fascinating engine designs too. You have to scroll down to the "Easter" section, but you'll find all sorts of curious oddities, inclucing a look at Volkswagen's "W-12" (an actual production engine), that was essentially two VR6 engines mated to the same crank.

^The delta engine is actually the Deltic diesel made by Napier. Rather successful in marine and some limited railroad use. Some good features, but comparatively high maintenance requirements. They had as many as 36 pistons, as I recall. No sleeve valves. No valves at all, actually.
The opposed piston diesel design was and still is quite successful. One of the best known is the Fairbanks-Morse 38D8 1/8. Used by many US subs in and after WWII. Still installed as emergency power on the navy's nuclear boats. Those were the first heavy diesels I worked on back in the '60's. The german Junkers Jumo was a successful aircraft diesel of the '30's and '40's of the same design. They may have originated the design, I think.
The vane pump design is very common. Probably every pump that moves propane or other flammables in north America uses that design, plus it is used in air starters on many industrial engines as well as air powered impact wrenches.
Did you know that Rudolph Diesel did not invent compression ignition and that the engine he was TRYING to design was not what we call the Diesel engine, which he did end up designing?

How about this one...


http://www.angellabsllc.com/resourse.html

It has been quite a long time since there has been an entirely new development of an internal combustion engine. The last one I saw was the rotary engine but this looks to be trully rotary. I think it is going to have a HUGE vibration issue but the small footprint looks impressive to me.

Thoughts?

Diesel designed and built the first bio diesel engine... that is kind of like saying that Edison designed and built the first Edison light bulb but none the less... He unsuccessfully wasted many years on designing a true Carnot engine. Either way his work on efficiency was one of the best lives spent on engineering.

O' and yes... KERS was not a green implementation... It was a green abomination… a cool demonstration of potential technologies that I truly hope that the FOTA union doesn’t keep from the field.

^I see cooling as one issue. That amount of horsepower and compression is going to produce a lot of heat, no matter how efficient the engine is. Piston lubrication is another. 26:1 compression is going to impose huge loads on the top ring, inside an aluminum cylinder. The top ring normally seats tighter as pressure increases. The pistons also have to move through the area of the cylinder where combustion has just occured. Any lubricant would have been stripped away. I haven't explored the entire site. These are just my 1st impressions. Still, I'm somewhat skeptical. This wouldn't be the first "miracle' engine, in need of funding, that was lubricated with large amounts of snakeoil.