How much Ad Blue are you using in your Euro6 car.....

[DanceswithUnix]

Urea is colourless, odourless and neither acidic no alkaline - oh, and pretty much non toxic.

It is also yet another fluid to put in the car, and another 10kg of weight + whatever the tank, pipes and injection control takes up. It's another system to go wrong.

Electric cars are looking more tempting by the day.

[Dashers]

Diesel? I'm not going to drive one of those toxic things. Unless I'm heading towards 20,000 miles a year it doesn't make sense.

Electric cars are great providing you aren't a motorway warrior. Next year's models will do 250miles. Mine won't do more than 100 miles, but it looks like I'll be able to upgrade the batteries next year to new tech.

[kalniel]

So here's a question: While we're happily doing our best to remove combustion by-products downstream, is there much research going into upstream techniques (aside from just cooling/pressure increasing)? Could someone use a zeolite sponge to remove nitrogen from an engine air intake?

[Zak33]

blimey..this escalated fast!!!

from diesels to urine to electric cars....awesome!

[DanceswithUnix]

Could someone use a zeolite sponge to remove nitrogen from an engine air intake?

Leaving almost pure oxygen to mix with the hydrocarbon fuel? That would basically be a rocket engine, I like your style

Exhaust gas recirculation is traditionally used to reduce the amount of oxygen in the intake gas. I believe the idea is to make use of the nitrogen to lower the temperature and pressure of combustion to reduce the NOX levels. I don't know if egr is still in vogue, it used to be an American thing but as all tricks needed to be explored seemed to turn up in European engine designs.

Was interested to hear that Fiat group are looking at "electric turbo chargers" on their newer cars. Wonder what that means, sounds like a supercharger to me, but using an electric motor blower to give boost at low revs sounds like an interesting way to get better control over intake airflow and effective compression ratios rather than the variable geometry turbos we are used to.

[kalniel]

Leaving almost pure oxygen to mix with the hydrocarbon fuel? That would basically be a rocket engine, I like your style

Exhaust gas recirculation is traditionally used to reduce the amount of oxygen in the intake gas. I believe the idea is to make use of the nitrogen to lower the temperature and pressure of combustion to reduce the NOX levels. I don't know if egr is still in vogue, it used to be an American thing but as all tricks needed to be explored seemed to turn up in European engine designs.

Think it's still used - you get the bonus of cleaning up some exhaust impurities as well. But off the top of my head I thought the main reason you want to bring down the temperature was precisely because of the nitrogen content in the intake and it'd react at high temps to become NOx. Remove that content, go hot and clean and you'd perhaps get higher efficiency as well. Possibly at the expense of engine durability. I think the downside is you have to flush out the zeolite at some point, which I bet produces NOx..

Was interested to hear that Fiat group are looking at "electric turbo chargers" on their newer cars. Wonder what that means, sounds like a supercharger to me, but using an electric motor blower to give boost at low revs sounds like an interesting way to get better control over intake airflow and effective compression ratios rather than the variable geometry turbos we are used to.

Audi already have this in the SQ7. Makes perfect sense.

[Xlucine]

I suspect an engine running a stoichiometric mix with pure Ox would melt, like how jet engines are run lean to protect the turbines. Any N that goes get in would be bound to oxidise super fast. You'd need one hell of a scrubber to feed a diesel engine on nitrogen free air - there's no throttle butterfly in a diesel, since they need high pressure to initiate combustion, so they suck as much air as possible all the time (hence the significant difference in air filter sizes between a diesel and a petrol engine). You might get away with it thanks to some magic involving partial pressures, but I doubt it.

An electric motor on the shaft of a turbo could be really useful - getting a turbo that works at all RPM's on a petrol car is hard. A turbo that gives good boost at high RPM will not do much at low RPM, and a turbo that gives good boost at low RPM will blow up your engine at high RPM. With an electric motor involved, you can drive it as a supercharger at low RPM and then use the motor as a regenerative brake at high RPM to prevent knock.

[DanceswithUnix]

An electric motor on the shaft of a turbo could be really useful - getting a turbo that works at all RPM's on a petrol car is hard. A turbo that gives good boost at high RPM will not do much at low RPM, and a turbo that gives good boost at low RPM will blow up your engine at high RPM. With an electric motor involved, you can drive it as a supercharger at low RPM and then use the motor as a regenerative brake at high RPM to prevent knock.

The interesting bit was on here: https://en.wikipedia.org/wiki/Alfa_R...a_(952)#Models where it said

The top version will have 350 PS and will be equipped with 48 V battery because of electrical turbocharger and will be offered solely in North American market under the Veloce moniker.

Now that is quite a lift from the standard 280PS out of the 2.0l petrol engine, and you don't need 48V to blow a bit of air at low rpms.

Part of me does wonder though, if you have the weight penalty of 48V worth of batteries, why not just dump them into a 70PS worth of electric motor in a hybrid drivechain to make up the difference.

[Xlucine]

Err, [citation needed] - that bit of the page doesn't have any, all the press releases linked only mention the 280ps version

[kalniel]

Part of me does wonder though, if you have the weight penalty of 48V worth of batteries, why not just dump them into a 70PS worth of electric motor in a hybrid drivechain to make up the difference.

With the Audi system the batteries are li-ion rather than lead, so presumably not a big increase in weight.

[Apex]

No idea Zak, its a fill it once every 36k miles of so and its about 80 quid for the kit (1.6D PSA engine) This is on a 58plate Volvo V50 (think the 09 / 59 plates moved to a dry dpf setup over the wet dpf + adblue or what ever they call it)

[CAT-THE-FIFTH]

Euro....

[Apex]

Yeah i kinda picked up on that after the fact, not sure if this is a euro 4 or 5 engine now.