Turbine Engine: No Pistons, no lube, 30% better on gas! 1

[patprimmer]

I think the increases in crash survival in F1 and many other forms of motor sport are more to do with lots of details of design, support and equipment than the carbon fibre pod.

Things like:-
HANS devices.
Helmets.
Seat belts.
Fire extinguishers.
Run off areas.
Angles of barriers to direction of travel.
Soft barriers.
Rescue crews.
Fuel cells.
Drivers apparel.
Rigid pod surrounded by energy absorbig items that crumple or break of thus absorbing energy from the impact.




Regards

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[globi5]

That may be true, but I don't remember seeing Aluminum monocoques staying in one piece after hitting a wall at 260 km/h.

 

[patprimmer]

Gobi

There is a LOT more to the properties of a composite structure than the properties of just one component.

Fibre to resin ratio.
Type of resin.
Chemical types of fibre.
Geometry of fibre.
Surface coatings on fibre.
Fibre orientation.
Yarn structure.
Fabric structure.
Other components that may be used as fillers or laminated layers, like hard shins or lightweight cores or stringers or ribs.

F1 has acces to very high budgets and can afford complex designs and short if highly stressed life of components.

Everyday drivers are best kept relatively simple and cheap and need long life at low stress. Carbon fibre composites have a long way to go to offer value in everyday drivers.

Bottom line.

Refer back to greglocock's post eighth of July


Regards

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[globi5]

That's what I kept on saying:
The cost of carbon fibre is the problem and not the mechanical properties of the material.

Besides, F1 uses epoxy resins, fibre forge uses injection moldable thermoplast, which is obviously less costly but may still be more expensive than steel.

On July 12th I posted lots of facts. I simply prefer facts over opinions.

Btw, Toyota just made a light weight car out of carbon fiber reinforced plastic with a curbweight of only 440 kg, showing that weight can be reduced significantly:

http://www.edmunds.com/insideline/do/News/articleId=122972

Again the costs may be too high, but do you suggest that the lightweight, rigidity and structural safety claim is a scam from Toyota?

 

[patprimmer]

Thermoplastics or epoxy typically cost less than 20% of the price for carbon fibre, and the composites typically consist of over 50% fibre, therefore the carbon is a much more significant factor than the resin re costs.

The thermoplastic matrix composites are generally somewhat down on most physicals vs epoxy matrix, but they have a very significant benefit in that they can be thermoformed, but this also severely limits design possibilities as they can only be formed into a simple shape.

One problem with manufacturing thermoplastic composite sheet with fabric reinforcement is wetting the fibre wit the resin to get a good bond. With thermosets, there is time to work the resin in and the air out.

Regards

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[GregLocock]

Lotus use (or at least used) RTM, it was their vehicle weights I was thinking about. The problem there is that the glass fibre is largely unstressed, the backbone takes a lot of the load.

Some of the problems with designing carbon fibre monocoques that are efficient and crash proof are: surface finish, integration of hardpoints, post yield behaviour, refinement.

The second of those problems is so great that I would be tempted to integrate the suspension arms into the layup, ie use composite hinges, and carbon fibre arms.

In practical terms if you are interested in panel properties (ie out of plane stiffness) then the gain in going from S glass to CF is small.



Cheers

Greg Locock

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