13 replies to this topic

[Ali_G]

I've heard all the pluses to this new system lately. One being to increase revs.

But lets be honest. The new 111 degree Renault engine is supposed to lower the COG considerabley. But the new Valve system will easily counteract this. All it will do is replace a need for a camshaft. But it is being replaced with a technology which is far too bulky and cumbersome to be of any use. You don't really want to be putting so much mass so high up in the car.

I am also curious about this. Will the coils work straight off of the battery. Surely that would be a huge drain of power.

Niall

[desmo]

I seriously doubt that the new Renault engine utilises electromagnetic valve actuation. The Regie are being tight-lipped about the new engine so far though.

I am not convinced that the valvetrain is the limiting factor in a modern F1 engine today, although I am not really sure what precisely is. Inertial loads and frictional losses are a function of speed squared and power loss with inertia is friction times speed, in other words speed cubed. It appears to me that a point of diminishing returns is drawing near as far as producing power through more revs are concerned. Of course people have been saying this for years and yet the engineers keep finding ways of making higher revs work. I also wonder if localised gas velocities in the intake valve-valve seat region may be approaching sonic velocity which is as far as I know a brick wall as far as volumetric efficiency is concerned.

Anyone care to throw their two cents worth in on this one?

[Ali_G]

Desmo: So to increase revs you must all at one time.

1. Have valves which can open and shut faster.
2. Have a slippier cylender and piston head.
3. Have lighter compontents.
4. Faster air going into the cylender.

So in order to increase revs must all F1 engines improve in every area above.

And to be quiet honest today using such materials wouldn't there be a limit on how far they can reduce frictional forces with in the each cylender. Is this the stopping point for higher revs in F1 today.

Niall

[Jaxs]

I think this subject has has been examined before with mixed results,
Valves to open & close faster/ less friction;
The contradiction regarding friction losses, if electromagnetic valve operation replaces camshafts the reduction in friction is considerable. The weight addition has to considered against the reduction in the loss of four camshafts,cam covers, timing covers, drive chains, timing gears, tensioners, valve springs, camshaft bearings, nuts, washers, etc, etc,. Regie Renault have proved that lateral thinking and the implementation of new ideas have been beneficial in their search for the extra power and reliability.
Faster air;
I made a comment regarding air flow and it's importance in the thread regarding 'valve operation animation'. The air flow speed and movement is essential in the chase for more power.
Lighter components;
The composition of the reciprocating parts is another area under constant development, the use of ceramics in pistons began in the turbo days and has developed since. The use of computerised CAD and CAM programmes together with leading metalurgists have proved a distinct advantage to the leading teams.

The teams are searching for and implementing new ideas on a constant basis, without this the times and speeds would become constant.

Jack.

[Ali_G]

i was just thinking last night and I think I have come up with an idea for the Valves in and F1 engine.

To help with the repeated opening and closing of valves why not have 8 valves per cylender in an F1 car. So 4 for air and 4 for exhaust. The thing is then that only 2 valves will be used per rvolution. So each valve will only be doing half the work it used to.

Niall

[P1 Senna]

Current F1 Technical regs limit valves per cylinder to a maximum of five. And I really don't see how this scheme would provide any benefit. It would add even more complexity to an already very complex valvegear system.

It would also reduce the amount of airflow possible by having to reduce the size of the valves to fit them all into the combustion chamber, and then have only half of the valves operating at any given time.[p][Edited by P1 Senna on 12-30-2000]

[Yelnats]

Any considerations of using Electromagnetic valves in a F1 car should include a reference to the fact that there is no evidence that anyone has got one to operate above 7,000 rpm. The only witness to an operating EM valve engine I have found was one running in a Ford pickup designed by a Texas engine development company. It peaked at less than 5k and sounded like it was trying to hammer it's self to death!. And any reduction in friction by EM valves must be offset by the energy absorbed by the onboard generation of the huge currents required to open and close the valves at high RPMs. A pneumatic valve system uses a certain amount of energy storage and recovery whereas the EM vals are a total loss system. Obviously I don't have high hopes for seeing EM valves in F1 in the next decade but I's love to be proved wrong!

[Ali_G]

Yelnats: But wouldn't the usage of an EM Valve Acctuator, end havind some of the torque taken away from the Crankshaft to rn the camshaft. Wouldn't there be some sort of improvement with HP output.

Niall

[Yelnats]

I don't believe there will be any gain in net power because the crank, though relieved of the burden of a valve system, is going to have to drive the bloody great alternator needed to generate the massive electrical currents requred open and close the 40 EM valves at 17k rpm.

[Ali_G]

Would there be any sort of battery which could store enough energy from the start of the race.

Also what about in the system itself. When the valve will open electricity will be used. But when the valve is closing couldn't you just make electricity from this aswell.

Niall

[Yelnats]

Theres a possiblilty of using the back EMF (Electro Magnetic Force) of the moving valve to generate power and at the same time decelerate it but the cost in complexity is huge and would require high temperature zero resistance materials and other technologies such as light weight high capacity capacitor and a few other technologies that haven't been developed yet. I'm not saying EM valves are impossible but surprisingly, most technologies in F1 are pretty well proved in other areas before they make an appearance there. EM valves are no where near that stage yet.

[Ali_G]

I know that I am now approaching on CART teritory but I have an idea about how to harness the power of springs as acctuators more.

How about using the potential energy in the compressed springs to drive the Camshaft when the valve is closing. I know it would be a complicated system. Probabely envolving a gearbox and differential between crank and camshaft.

Of course to start it going the cam shaft would need some torque from the crankshaft. But after that less torque would be needed to drive the camshaft as some of its power would come from the release of energy from the springs decompressing after the valves closing.

Do any of ye think that this could be a viable idea or would the gain in HP not be worth it.

Niall

[Alvega]

Ali_G,

That's exactly what happens now with conventional valve actuation systems. The potential energy stored in the compressed spring is partially recovered through the cam to the camshaft when the valve closes. Of course not all the energy is recovered, due hysteresis and friction losses.

[Ali_G]

Really. Obviously not in such a technical and comlicated way I presume.

Niall