Vehicle Development Project - Interests

[WhiteBlue]

If you look for fast solenoid direct drivers have a look at Parker's voice coil technology. They are available in cartridge design which would be good for multi cylinder design.

http://www.engineerlive.com/Process-Eng ... ogy/22450/
http://www.parker.com/literature/Hydrau ... 3334DE.pdf



I believe they are unique and push proportional valve performance right into the fields where you would be using Moog servo valves usually.

I would also have a look at Ferrari's conical cams which are engaged by shifting the cam shaft hydraulically along it's axis. The other technology of potential concern would be Porsche's variable valves which are mentioned and explained in their Cayenne S 2010 brochure.

The thread which mentions much future F1 technology is at viewtopic.php?p=191814&f=4#p191814

[alexisgreene]

I have not heard of voice coil technology before. This is very interesting to me. I have read a number of the manuals but can not find an actual open-close or close-open time in milliseconds. The solenoid valves I had chosen to use have response times of 80 ms energized and 30 ms de-energized. These were SV10-21 and SV38-38 by HydraForce. I chose to use these last year so I am not surprised that there have been improvements. I would really need to get those response times to do some calculations and estimate performance. I will keep looking around but if you have more information on them, that would save me a lot of time. Thanks a lot for the great links!

[alexisgreene]

I have done some snooping and got the step response times.

D31FP - 10 ms
D41FP - 13 ms
D81/91FP - 19 ms
D111FP - 45 ms

These are amazing compared to the response times I listed earlier. Now I am going to check up on their maximum operating pressures. I was looking for something that can handle about 3000 psi (roughly 200 bar), but considering I do not plan on turbocharging or using nitrous on this engine until I actually get the valves function properly, I can get by with about 1800 psi (roughly 120 bar).

I may be wrong, but these will be the cylinder pressures that the actuators will have to overcome in order to open the exhaust valves.

[WhiteBlue]

I knew that the voice coil valves are bloody fast because they have been used in light alloy die casting.

[ahmedvortex]

i'd loved to help you , i'm working on magnetic valve system able to be adjusted faster than a pneumatic one , but hard time with the electric power unit supplier , and the motec unit to manage it .

[alexisgreene]

I have been considering going electric instead of hydraulic but the power requirements would be too much for a standard 12 volt system. I decided it would be easier to solve pressure and flow issues on start-up than it is to design a high voltage system from the ground up.

[J.A.W.]

'Voice coil' actuation has - in fact - been in commercial use for the past decade..
.. by high speed BRP E-TEC 2-stroke Direct Fuel Injection for Evinrude & Ski-doo water & snow-craft powerplants..

[J.A.W.]

Here is a recent attempt at utilizing voice coil/mechanical drive poppet valves in a variable timing scheme..

http://www.launchpnt.com/portfolio/tran ... -actuator/

[MrPotatoHead]

The two biggest problems with using electromagnetic control of poppet valves are the response time and the inertia of the valve assembly.
The response time quoted in the voice coil experiments is 2.5ms - that is at least an order of magnitude above where it would need to be to be useful imo.

[J.A.W.]

Yeah, poppet valves have a number of problematic issues - which have been well-known for many decades..
..regrettably however, current F1 G.P. competition reg's explicitly constrain/proscribe alternatives..

& a carefully prescribed rules set.. was supposedly predicated to enable a 'level playing field', but as has been shown..
..this is, in reality.. far from the case.. which the Championship results clearly demonstrate..

[MrPotatoHead]

Yeah, poppet valves have a number of problematic issues - which have been well-known for many decades..
..regrettably however, current F1 G.P. competition reg's explicitly constrain/proscribe alternatives..

& a carefully prescribed rules set.. was supposedly predicated to enable a 'level playing field', but as has been shown..
..this is, in reality.. far from the case.. which the Championship results clearly demonstrate..

It would be amazing if the rules were relaxed a little more to involve options like rotary valves.
The inertia involved in a rotary valve is far less than a poppet valve and probably has more scope for electromechanical implementations.

I've always been tempted to make a rotary valve test engine.
Sealing of course is the problem on rotary valves.

[J.A.W.]

Koenigsegg came up with a 'freevalve' camless oleo-pneumatic design, but still using poppet valves..
..whether it is actually a practicable device, in both functional efficiency & durability terms - is another matter..

[MrPotatoHead]

Koenigsegg came up with a 'freevalve' camless oleo-pneumatic design, but still using poppet valves..
..whether it is actually a practicable device, in both functional efficiency & durability terms - is another matter..

https://i.ytimg.com/vi/NJjgdvfXuJA/hqdefault.jpg

I feel their system is hyped up a little too much at this stage.
But it will be interesting to see.

[godlameroso]

I think it could work with more pedestrian rev ranges of around 5,500 - 7,000 rpm, engines with long strokes, but not at F1 speeds.

[J.A.W.]

I think it could work with more pedestrian rev ranges of around 5,500 - 7,000 rpm, engines with long strokes, but not at F1 speeds.

Yet at those modest suggested rpm - is there really a significant advantage, in either valve timing/flow, or efficiency?

Regular high-longevity production engines using self-adjusting hydraulic lash VVT cams of such rpm range use..
..viz: the M-B M-104 DOHC 4V six cylinder, were available over a 1/4 century ago..

& one of the reasons F1 went back to forced induction was the overt inefficiencies of poppet valves..
..which showed in costly, short-life componentry, plus frictional , & gas flow-wise.. when used by ultra-high rpm N/A 4Ts..

Reasonable engineering alternatives - such as 2T, or even 4T sleeve/rotary valves, were quickly proscribed, 'of course'..