F1 Tech Is About to Make Buses More Efficient
wired.com
wired.com
As an example, my regular bus route is 50% highway at 80 km/h and 50% urban start-stop traffic. The city buses have a huge turbo diesel or natural gas engine, and the turbo takes about 3 seconds to spool up. At 80 km/h, drivers tend to be pumping on and off the throttle, purging the turbo pressure repeatedly. This is horrible for fuel efficiency.
Ideally, an electric motor should do the initial few seconds acceleration, while the turbo is being spooled up using the electric motor attached. When the turbo is spools up, the internal combustion engine should be slowly introduced by adding fuel according to the correct stoichiometric ratio. At cruise speeds, engine power could be regulated by harvesting energy off the turbine rather than pumping the gas pedal which purges the whole turbo.
A city bus should be able to operate at or near optimum stoichiometric conditions at all times, saving a ton of gas and emissions. Currently there's a huge puff of black diesel smoke every time the bus leaves a bus stop.
These are very exciting times for anyone who is interested in motor sports technologies applied to efficient transport.
Diesel motors operate quite differently than gasoline engines in this regard, actually. A diesel motor is only operating at the correct stoichiometric ratio at full throttle and is running lean for the rest of the time because there is no throttle plate to modulate air intake and power is only modulated by the quantity of fuel injected into the cylinders.
If they claim to save 20% on fuel, then a single bus would save about $10k/yr, and if the system can pay for itself in three years, then it would cost about $30k.
These mileage numbers aren't for London, so that estimate could be off by quite a bit. Still, consider than a standard diesel bus may cost $250k in the US while a hybrid 40' bus could cost $600k,[1] and this looks like a great deal.
[1] http://www.intercitytransit.com/SiteCollectionDocuments/hybr...
There have been long articles about flywheels every now and then, yet you never see them in buses.
At least that would be my assumption given the trend of hybrid vehicles and lack of comparable change in larger ones. F1 uses much stronger engines so maybe the tech is more directly usable.
A jet turbine rotate at speed in excess of 50k rpm. In the event a blade broke off, it could sale though the outer casing, your body, a cement wall, before you could hear the engine exploding.
Yet... that's perfectly safe. All I'm saying is mechanical engineers are VERY good at their jobs.
In diesel engines, if there is a runaway and it isn't stopped the shaft can get overstressed and literally explode.
Jet engines are specially armored not to let any part of the turbine escape the casing in case things go wrong (yet it still happens http://www.avherald.com/h?search_term=uncontained&opt=0&dose... quite a lot one might say). And quite a lot of R&D was put into it not happening.
Is there enough R&D being put into the flywheel not failing?
EDIT: my point is that stuff that is OK in a racing car might not necessarily be safe enough to put on a bus or a tram
The famous saying, "To earn a small fortune in F1 racing, you must first spend a large one." Is very telling of this. F1 isn't done to make F1 go fast, its done to make other cars go.
:.:.:
A standard durability cell for engine testing for a production engine component will typically have a ~20-30 year old sensors, and 15-20 year old data acquisition system.
F1 all components will likely be <5 years.
There's two types of flywheels I'm aware of that are failsafe. The first is a tape flywheel. On failure it unwinds inside the container. The other type is a system where the disk is made of powdered ceramic. In the event of overload it turns to dust.
A paper I found online suggests the F1 system uses a powdered ceramic disk: http://136.142.82.187/eng12/Author/data/2097.docx
Motorsport is arguably a latecomer to mechanical batteries, which have been used in vehicular, transport, industrial, and aerospace applications for a long, long time.
Add incompetence of local politicians and the far higher cost of renewing together and upgrading existing fleets is probably often a better move. Obviously it isn't an extreme long term solution though.