F1technical.net

noname wrote:

WhiteBlue wrote:Not any more. The advanced manufacturers of small axial turbines do the whole wheel out of one solid piece with 5-axis cutting.

You can have fully machined turbine wheel but, to my knowledge, the process is being used mainly to make TiAL wheels (or lower temp. applications). And ceramic materials are banned (except stuff like bearings).

Materials used for high temp wheels (they will, I think, work above 1000degC) exist only as casting. They are machined (contour, back side, etc.), but they are not made from the billet. However wax patterns are made on 5 axis CNCs.

Compressor wheels, on the other hand, are fully machined.

neilbah wrote:ok to settle the argument we'll use a mixed-flow compressor or 'diagonal flow' one which is a combination of the axial and radial compressors

neilbah wrote:i think the system would use vanes that could change angles, as the turbo spools and accelerates,different stages kick in...

mx_tifoso wrote:WB, what's the reasoning behind that? Just another rule to prevent excessive power/speed?

WhiteBlue wrote:

mx_tifoso wrote:WB, what's the reasoning behind that? Just another rule to prevent excessive power/speed?

AFAIK the restrictions were put in place to limit initial development cost. Cosworth belongs to the engine suppliers and they are not going to have deep pockets. I guess they simply left those refinements for later when the initial costs for developing the engine have been amortized.

Excessive power/speed would be better reigned in by further fuel cuts.

flynfrog wrote:

noname wrote:

WhiteBlue wrote:Not any more. The advanced manufacturers of small axial turbines do the whole wheel out of one solid piece with 5-axis cutting.

You can have fully machined turbine wheel but, to my knowledge, the process is being used mainly to make TiAL wheels (or lower temp. applications). And ceramic materials are banned (except stuff like bearings).

Materials used for high temp wheels (they will, I think, work above 1000degC) exist only as casting. They are machined (contour, back side, etc.), but they are not made from the billet. However wax patterns are made on 5 axis CNCs.

Compressor wheels, on the other hand, are fully machined.

You can still machine High nickle alloys in a single piece system.


single piece wheels are generally done when turbines become to small to easily cast and a assemble its mostly for weight savings and manufactuability.

in smaller applications the centrifugal compressor is used to cut down rotating mass of multiple stages. As size goes up the inefficiencies start to climb and the weight savings advantage is lost. There is still the packaging benefit that might be worth more then we think in a cramped f1 car.

Muskrat wrote:Are the new 1.6 V6 Turbos 1 or 2 turbo lumps - was hoping 2 one hanging off each side ala most of te 80s ones.

wuzak wrote:

Onch wrote:

manchild wrote:...
Perhaps the ultimate configuration would be to have primary turbine located at the end of the engine, just above the clutch with the axle along the bottom of V (within the engine block), while the compressor would be at the front end of the engine.
...

Unfortunately I do not think the shaft linking compressor and turbine can be made stiff and dynamically balanced enough to run at x00.000rpm for more than a couple of seconds before exploding. .

Plus you'd have to design some axial and radial freedom in as the block will vibrate, expand under load, twist and bend in the corners etc.

By the time you have designed a shaft that can handle all these parameters the inertia will have increased so much that the turbocharger will not be practically usable.

I don't think a shaft of that length, transmitting the amount of power it needs to is such a problem.

After all early Rolls-Royce Griffons used a torsionally flexible shaft that ran from the front of the engine to the rear of the engine to drive the supercharger. It would have been the best part of 2m long, and transmitting somewhat more power than this one would be required to. And they were running slower, so had to deal with more torque.

Napier Sabres also used torsionally flexible shafts to drive the supercharger. In that case the pair of shafts ran inside the shafts that drove the sleeve valves.

Axial displacement is also not so much an issue, IMO. A simple splined joint should work fine.

Remember that the turbo shaft also has to drive the MGUH. This can be fitted with a clutch and gears. It would be possible, therefore, to mount the MGUH coaxially with the turbine shaft and within the vee.

The only issue with this layout is that getting air into the compressor is compromised. I would think that, providing the compressor housing is small enough, that the shaft would be shorter, and the compressor in the vee, allowing for a better inlet design.

Alternatively, If you reverse the compressor, such that the inlet is between the compressor and the turbine, you could havnge the MGUH off the front.

Scarbs wrote:At the IMIS show in Indianpolis, Simon showed another image of the engine. Simon explained to RET that the compressor may end up sitting ahead of the engine, with a shaft linking it to the turbine running through the engines “V”. This will keep the compressor in a cooler location and allow for even shorter, tidier pipework. Albeit at the expense of a longer and heavier turbine shaft, with potential torsional and inertia issues when the turbo spools up.

matt21 wrote: .....I don't think a shaft of that length, transmitting the amount of power it needs to is such a problem.....