F1technical.net

irsq4 wrote:

ian_s wrote:i dont see how they can disconnect the compressor and the turbine, that would break 5.1.6

5.1.6 Pressure charging may only be effected by the use of a sole single stage compressor linked to a sole single stage exhaust turbine by a shaft assembly parallel to the engine crankshaft and within 25mm of the car centre line. The shaft must be designed so as to ensure that the shaft assembly, the compressor and the turbine always rotate about a common axis and at the same angular velocity, an electrical motor generator (MGU-H) may be directly coupled to it.

Here says shaft assembly...can you then have assembled shafts like one in one and clutch them, then you could separate compressor and turbine?

Shaft assembly such that the turbine and compressor rotate at the same speed at all times.

This allows the separation between turbine and comressor as in the Mercedes with more than one shaft and a support bearing in between.

The other thing is that the turbine and compressor do have to be co-axial.

xpensive wrote:But seriously, a clutch between the MGU-H and turbine is the only way to xplain the log-xhaust with retained throttle-response.

Programming/mapping/testing/sorting is another explanation.

Sigh, I'm afraid you still don't follow my thinking wuz. The idea with the roller clutch between the MGU-H and turbine, on a split turbo, is the ability to leave the turbine's inertia behind for a quick spool-up of the compressor, using the MGU-H only.

As soon as the turbine is up to speed, the roller clutch will connect again and the turbine will take over running the compressor.

This way you can employ log-xhausts for a compact installation, as you are not dependent on the turbine for throttle-response.

Torque, are you kidding, at 50 kW and 100 000 rpm we are talking less than 5 Nm.

Brian Coat wrote:Facts Only.

Does your earlier statement include no turbo-to-MGU-H clutch?

Facts:

Yes.

A roller clutch is not legal, the compressor and turbine must rotate at the same speed at all times, there is no loophole.

The FIA have design data and a homologated engine to compare it to, they can also compare this engine to any engine during the season to confirm they are still legal.

Discussion Point (non-preffered):

If the MGUH-Turbo system is fully optimised (which they are aiming for) the MGUH will always be either Powering or Harvesting, it always dictates the Turbocharger shaft speed so a clutch is of no benefit.

Facts Only wrote: ...
A roller clutch is not legal, the compressor and turbine must rotate at the same speed at all times, there is no loophole.

The FIA have design data and a homologated engine to compare it to, they can also compare this engine to any engine during the season to confirm they are still legal.
...

I still beg to differ.

wuzak wrote:

WilliamsF1 wrote:if a clutch is used on the system, wont the entire thing stall each time when the system is engaged?

The clutch is probably used only to disengage the ers-h where there is issue with the entire ers like we saw in Canada with mercs

It shouldn't if the MGUH is spun up to a matching speed before engagement.

I think there may be a small band where the turbine and compressor are matched well enough such that there is enough excess power to continue accelerating the turbo but not enough worth extracting via the MGUH. During that band they may disconnect the MGU.

In any case, the manufacturers would probably zip past that point using the MGUH to drive the turbo up to speed faster and then switch over to generating as soon as possible.

The idea which x has is there are 2 clutches on the system

turbine - clutch - mgu - clutch - compressor

in such a system when the turbine is disconnected, it will speed up much faster than the turbine assisted by the mgu. The turbine speed is also going to be limited to 125,000 rpm while the turbine is free wheeling well beyond that. use a clutch at this moment, it will stall.

WilliamsF1 wrote: ...
The idea which x has is there are 2 clutches on the system

turbine - clutch - mgu - clutch - compressor

in such a system when the turbine is disconnected, it will speed up much faster than the turbine assisted by the mgu. The turbine speed is also going to be limited to 125,000 rpm while the turbine is free wheeling well beyond that. use a clutch at this moment, it will stall.

Again, 50 kW at 100 000 rpm is less than 5 Nm, no turbine will stall from that torque. Moreover, with the roller clutch it will be a very smooth and automatic transition when the turbine comes on song catching up with the MGU-H speed-wise.

xpensive wrote:Sigh, I'm afraid you still don't follow my thinking wuz. The idea with the roller clutch between the MGU-H and turbine, on a split turbo, is the ability to leave the turbine's inertia behind for a quick spool-up of the compressor, using the MGU-H only.

As soon as the turbine is up to speed, the roller clutch will connect again and the turbine will take over running the compressor.

This way you can employ log-xhausts for a compact installation, as you are not dependent on the turbine for throttle-response.

Torque, are you kidding, at 50 kW and 100 000 rpm we are talking less than 5 Nm.

The roller clutch is interesting I must admit. I think though you could clear up a few things with a drawing

Off the current discussion

It will be cool if someone used a compressor fused to a radial rotor



While I was surfing; I also found this

http://www.google.com/patents/US20030084888

xpensive wrote:

WilliamsF1 wrote: ...
The idea which x has is there are 2 clutches on the system

turbine - clutch - mgu - clutch - compressor

in such a system when the turbine is disconnected, it will speed up much faster than the turbine assisted by the mgu. The turbine speed is also going to be limited to 125,000 rpm while the turbine is free wheeling well beyond that. use a clutch at this moment, it will stall.

Again, 50 kW at 100 000 rpm is less than 5 Nm, no turbine will stall from that torque. Moreover, with the roller clutch it will be a very smooth and automatic transition when the turbine comes on song catching up with the MGU-H speed-wise.

Maybe you are right, but should torque be the only consideration?

I also feel speed control will be an issue.

My question is why disconnect the turbine at all? it hardly has a mass to it spinning it with the MGU along with the compressor should hardly be an issue.

Inertia and windage, as xhausts move slower than the turbine-wheel, disconnecting the turbine at spool-up makes a lot of sense.

Steven wrote: ...
The roller clutch is interesting I must admit. I think though you could clear up a few things with a drawing

Thank you esteemed Owner.

Afraid this from Schaeffler's web-site is all I've got for now, but it's basically a needle bearing with the needles tangentially spring loaded against a wedge, locking it in one direction and rolling in the other. The side rollers are for radial support only.





http://www.schaeffler.com/content.schae ... utches.jsp

it seems that from 2015 there will be an F1 race on the track in Mexico City

are the PUs suitable for this (high altitude - Austria and Brazil ? have a bit of altitude too)
eg turbo etc rpm
ie will PU power be more than elsewhere, or less ?

the cruise efficiency of the Wright TC was higher with altitude than at sea level, presumably due to greater recovery

Tommy Cookers wrote:are the PUs suitable for this (high altitude - Austria and Brazil ? have a bit of altitude too)
ie will PU power be more than elsewhere, or less ?

Even if you have a lower air density you can compansate by higher boost. But as fuel flow is limited the power will be the same.

xpensive wrote:Sigh, I'm afraid you still don't follow my thinking wuz. The idea with the roller clutch between the MGU-H and turbine, on a split turbo, is the ability to leave the turbine's inertia behind for a quick spool-up of the compressor, using the MGU-H only.

As soon as the turbine is up to speed, the roller clutch will connect again and the turbine will take over running the compressor.

This way you can employ log-xhausts for a compact installation, as you are not dependent on the turbine for throttle-response.

Torque, are you kidding, at 50 kW and 100 000 rpm we are talking less than 5 Nm.

What about the requirement for both wheels to rotate with the same angular velocity at all times? If I understand correctly what you describe it's clear breach of the regulations.