Paramagnetic nanodot smartstuff offers 1TB micro-SD cards Boffins in America say they have developed a new material which will mean terabyte-capacity micro format data cards. Intriguingly, the same wonder-stuff could also be employed in building super-high-temperature, super-efficient ceramic car engines. Smart-structures wiz Dr Jagdish Narayan, who is fortunate enough to be "John C …
These are a long way off if ever. It isn't as cut and dried as higher combustion temperatures = more efficiency/power sadly.
a) metal is cheap and easy to cast + machine
b) ceramics are hard (read expensive) to tollerance because sintered powders shrink during the curing process and the final products are then difficult to grind/machine
Combustion temperatures are already in excess of the burn temperatures for aluminium in regular road car petrol engines. One reason why they survive at all is that a thin layer of unburnt air/fuel coats the inside of the cylinder and acts as insulation. Hotter temps, detonation (explosion rather than gentle controlled burn) or pre-ignition disrupts this layer and then burns pits into heads/pistons. The ECU will back off the ignition timing to prevent repeated det in the same cylinder from destroying the engine in a matter of seconds.
This insulating layer is disrupted/non existent in high temp/pressure ceramic engines causing greater heat loss through conduction and an associated loss in efficiency and increase in block cooling requirement.
You gain on the swings but lose on the roundabouts :(
...but how do you address these bits? I might as well claim that the suds in my dirty coffee cup contains PetaBits of storage in their arrangement of electron spins, but I don't happen to have a read/write head that can address the electrons in question.
It seems to me that this research isn't offering anything new.
I imagine, that since the nano-wassits are already in a semiconductor, these things will act like flash chips, without a read/write head at all.
I sure hope the 1TB microSD cards do better than the 9MB/s write rate that I get on my current ones... I hope even more that these things are /very/ fast, so they can be used for actual high end storage instead of just ludicrous usb drives.
Engines these days are more than capable of achieving this sort of figure... but the consumer and political need to make cars safer and have more gadgets to make them safer and more fun... has added huge amounts of weight to your average vehicle.
Take a modern fuel efficient engine of say 1.6 or 1.8lts and stick it in a car from 20-30 yrs ago that had the same sized engine... and you'll see just what a difference it makes.
Like the guy who dropped a 2lt Honda engine into an old Ford and was getting 50 mpg and upwards... the car was 200kg's lighter.
I know some will harp on about crash cells and safety features... but cars can be built strong and safe with lighter materials at not much extra cost these days... Some are already using plastics on certain body panels... and still these cars are heavy lumbering beasts that can barely match the MPG's of cars from 20yrs ago.
Here's another example... I owned a 1990 Ford Sierra 1.8lx and on a run it would do 39mpg that's 70-80 mph for 400 miles.
I now drive an 07 Mazda 3 1.8 TS2 and get 40 mpg on a run at the same average speeds.
I know for a fact the Ford engine in my old sierra was not a very efficient one, wasn't even fuel injected... The difference is in the weights of the cars... and the Mazda 3 is supposed to be the smaller of the two.
>This insulating layer is disrupted/non existent in high temp/pressure ceramic engines causing greater heat loss through conduction and an associated loss in efficiency and increase in block cooling requirement.
Ceramic is a poor heat conductor. Ideallly (yes, I know) a ceramic engine would have no cooling, and would be wrapped in insulation.
No heat loss (except via the exhaust) means all the energy is used to move the car, rather than 70% used to heat the air at the moment.*
A thick coat of ceramic on cylinder/piston/exhaust would be a tremendous start toward that goal. The metal underneath would of course have to be kept at the usual temperatures, just like now.
*Well all the fuel is used to heat the air if you think about it: when you have moved from A to B, *all* the moving energy has been spent in friction (mainly against air, tyres and brakes) which ends up heating the air.
This is the point that seems counter intuitive. Ceramic is a good insulator compared with say Al but it is piss poor compared to air. Several orders of magnitude worse in fact.
Air ~ 0.024 W/mK
Al2O3 ~ 5 - 25 W/mK (varies with temperature)
200 to1000x better thermal conductor.
Manufacturers already make ceramic coatings for aluminium pistons but these are more for preventing burn/pitting at hot spots (due to complex shapes e.g. pockets for valve clearance).
Ceramic coated exhausts are extensively used in motorsport already - thin layer though to reduce radiation I think more than anything. Air gaps between heat shields are the 'best' insulation. Rock wool etc. works because the air trapped not because the fibres are poor conductors.
80mpg is still a pretty impressive figure, so long as the guy's (a) talking about "proper" cars- your mondeo/3-series sized cars- rather than a tiny little mid-90s Fiesta/Corsa, and (b) factoring in the higher weight of a modern car.
If he's meaning "it'll do 80mpg in a one-man bullet-shaped vehicle" then... well, it's earth shattering for the Americans but we've got better over here...
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