[European] Diesel Dirty

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I always read that diesels had low NOx levels but high particulates this trade off was somehow worth it for emissions. I assumed that that's why there were so many diesel cars in Europe, because there were more efficient and less polluting because you could get by with a smaller displacement engine that produced fewer emissions.

I think that passenger car diesels might be going to way of the rotary engine, can't pass emissions anymore. Too many jobs on the line for anyone to admit it.
 
Originally Posted By: maxdustington
I always read that diesels had low NOx levels but high particulates this trade off was somehow worth it for emissions. I assumed that that's why there were so many diesel cars in Europe, because there were more efficient and less polluting because you could get by with a smaller displacement engine that produced fewer emissions.

I think that passenger car diesels might be going to way of the rotary engine, can't pass emissions anymore. Too many jobs on the line for anyone to admit it.


NOX is not why Diesels were pushed by Goverment in Europe.

Reduced g/km of CO2 was the reason, reduced CO2 to reduce Global Warming.

I would take all the anti diesel rhetoric with a pinch of salt.

The actual tailpipe emissions are extremely low in modern Euro6 diesels with AdBlue even when compared tp a Euro4 diesel from 10 years ago.

The EU is an unelected body of arrogant egotistical power hungry idiots.
 
Originally Posted By: maxdustington
I always read that diesels had low NOx levels but high particulates this trade off was somehow worth it for emissions. I assumed that that's why there were so many diesel cars in Europe, because there were more efficient and less polluting because you could get by with a smaller displacement engine that produced fewer emissions.

I think that passenger car diesels might be going to way of the rotary engine, can't pass emissions anymore. Too many jobs on the line for anyone to admit it.

It was before. Problem is high pressure direct injection. It is opposite of what one would assume. The lower consumption the more NOx.
But yes, diesels were pushed bcs of CO2, while creating slew of issues with NOx, including limestone detirioration which affects numerous historic sites, especially in Paris (just as an example).
 
Originally Posted By: edyvw
Originally Posted By: maxdustington
I always read that diesels had low NOx levels but high particulates this trade off was somehow worth it for emissions. I assumed that that's why there were so many diesel cars in Europe, because there were more efficient and less polluting because you could get by with a smaller displacement engine that produced fewer emissions.

I think that passenger car diesels might be going to way of the rotary engine, can't pass emissions anymore. Too many jobs on the line for anyone to admit it.

It was before. Problem is high pressure direct injection. It is opposite of what one would assume. The lower consumption the more NOx.
But yes, diesels were pushed bcs of CO2, while creating slew of issues with NOx, including limestone detirioration which affects numerous historic sites, especially in Paris (just as an example).


Wasn't NOx, it was SOx. Sulfation of limestone due to the sulfuric and sulfurous acids.
And at Uni, we were taught that diesels, with the high compression ratio and lean combustion were always more NOx prone.

There's some errors being driven in this thread.
 
Originally Posted By: Shannow
Originally Posted By: edyvw
Originally Posted By: maxdustington
I always read that diesels had low NOx levels but high particulates this trade off was somehow worth it for emissions. I assumed that that's why there were so many diesel cars in Europe, because there were more efficient and less polluting because you could get by with a smaller displacement engine that produced fewer emissions.

I think that passenger car diesels might be going to way of the rotary engine, can't pass emissions anymore. Too many jobs on the line for anyone to admit it.

It was before. Problem is high pressure direct injection. It is opposite of what one would assume. The lower consumption the more NOx.
But yes, diesels were pushed bcs of CO2, while creating slew of issues with NOx, including limestone detirioration which affects numerous historic sites, especially in Paris (just as an example).


Wasn't NOx, it was SOx. Sulfation of limestone due to the sulfuric and sulfurous acids.
And at Uni, we were taught that diesels, with the high compression ratio and lean combustion were always more NOx prone.

There's some errors being driven in this thread.

Both So2 and NOx gases are contributing. You are right, SO2 is the worst when it comes to corrosion, but other gases are also an issue:
http://www.air-quality.org.uk/12.php
And that is what I said, with direct injection comes more NOx. Remember first GDI engine in Mitsubishi Carisma? Huge issue was ridiculously high NOx. The reason why other fallowed much later was problem of solving Nox.
 
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diesel by nature are dirty engines, less powerful but more efficient. I have yet to see one that doen'st belch out black smoke irrespective of brand and year.
Commercial vehicles have been using them for ever & ever but they do mostly non stop long journeys.

To resolve the performance issue, passenger car engine started to be fitted with turbochargers.

They are unsuitable for short journies and extremelt poluttant (just try breathing the air next to a raw of diesels stuck at a red traffic light.

They require more maintenance to keep all the poisonous emmission under control. But in the real world people take shortcuts some even remove the DPF to improve on fuel economy. Price of fuel here is about £1.35/ litre

So naturally people floggeg towards diesel irrespective of it's suitability for theiir use in order to make substantial savings on their road tax (typically from £300 to £150 for a 2 litre car)

What was never highlighted to the public is that more CO2 is produced by the increased cattle farming, more is produced by burning huge areas of the rain forest.

WE have increased serious illnesses (allergic, respiratory even cancerous) linke to diesel engine polution
 
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Originally Posted By: bonjo
diesel by nature are dirty engines, less powerful but more efficient. I have yet to see one that doen'st belch out black smoke irrespective of brand and year.
Commercial vehicles have been using them for ever & ever but they do mostly non stop long journeys.

To resolve the performance issue, passenger car engine started to be fitted with turbochargers.

They are unsuitable for short journies and extremelt poluttant (just try breathing the air next to a raw of diesels stuck at a red traffic light.

They require more maintenance to keep all the poisonous emmission under control. But in the real world people take shortcuts some even remove the DPF to improve on fuel economy. Price of fuel here is about £1.35/ litre

At the height of global warming debate when it was a political hot potatoes (winning vites) or any organisation wanting funding (they would add "CO2 emmision"/ "global warming" to their application), our incompetant politicians/ ministers decided to heavily tax petrol car usage and give huge financial incentive to diesel passenger car buyers by changing the fixed yearly road tax payment to be based on CO2 emmission only!!

So naturally people floggeg towards diesel irrespective of it's suitability for theiir use in order to make substantial savings on their road tax (typically from £300 to £150 for a 2 litre car)

What was never highlighted to the public is that more CO2 is produced by the increased cattle farming, more is produced by burning huge areas of the rain forest.

WE have increased serious illnesses (allergic, respiratory even cancerous) linke to diesel engine polution

I am from Europe, Bosnia, where 80-90% of cars are diesels. Plus I grew up in city that has biggest steel plant in SouthEast Europe. When I go back home I always get reminder how dirty diesel actually is. But what really struck me was pollution in Paris. I was in Paris in March and April and air is like biting lungs.
 
No, not dirty Euro diesels...I think all the talk is from those from the US, who seem to have dirty diesels. I'd rather sit behind a diesel than a petrol vehicle, these days I don't smell a thing. Old Japanese diesels - now we are talking dirty diesel, those things were like a Leyland from the '50's.
 
Originally Posted By: edyvw

Both So2 and NOx gases are contributing. You are right, SO2 is the worst when it comes to corrosion, but other gases are also an issue:
http://www.air-quality.org.uk/12.php
And that is what I said, with direct injection comes more NOx. Remember first GDI engine in Mitsubishi Carisma? Huge issue was ridiculously high NOx. The reason why other fallowed much later was problem of solving Nox.


No, it was Sox...NOx contributed to photochemical smog at ground level, along with lung iritation, and (for eg. power station emissions acid rain..again, nothing like SOx)

It's nothing to do with direct injection, it's the nature of having nitrogen and oxygen at 3.76:1 molar concentrations exposed to high heat...they react, in a fast forward, slow backward reaction and leave the engine as various oxides of nitrogen...it was the CR and lean combustion of diesels that did it.

GDI came along and mimicked it...in modern "Engines that burn Gasoline"

NOx was easy...drop the cobustion temperatures...EGR came in in the early '70s for gassers. Water injection could have done it too.
 
This thread is so full of half baked opinions over fact, and those half baked opinions are based on 30 year information/opinion (like every diesel thread in BITOG that it needs a fork stuck in it.

Diesels, as we knew them are gone.

Modern engines "that run on diesel", just like modern engines "that run on gasoline" are so far removed from the engines that we knew 10, 20, 30 years ago...and are merging in technology rather than being totally separate.

I sat behind a 1976 Torana V-8 at the light the other day...my eyes were watering, in just one change of lights...
 
I agree with Shannow, most complaining about dirty diesels would probably be unable to tell the difference between a modern diesel and a modern GDI engine, while sitting inside a vehicle equipped with one.

Also, their tailpipes are super clean, no soot at all, opposite of GDI versions.
 
Originally Posted By: Shannow

Diesels, as we knew them are gone.

Modern engines "that run on diesel", just like modern engines "that run on gasoline" are so far removed from the engines that we knew 10, 20, 30 years ago...


A good example of the change is the Mitsubishi 4D56 - based on a petrol engine, the early 4D56, and earlier 4D55, were gutless, stinky and blew clouds of back smoke...I had one, I would watch my black smoke billowing out going up hills. The modern 4D56 is dohc, common rail has double the torque, NO smoke, and practically no smell, and the smell it has is nothing like diesel.

The new Ranger is going to be a 2 litre, with 500 nm of torque - they just keep getting smaller, and more powerful.
 
Originally Posted By: KrisZ
I agree with Shannow, most complaining about dirty diesels would probably be unable to tell the difference between a modern diesel and a modern GDI engine, while sitting inside a vehicle equipped with one.

Also, their tailpipes are super clean, no soot at all, opposite of GDI versions.

Well, no soot thanx to DPF. Take DPF out like people do, and you will see what happens.
Truth is, the NVH of both diesels and gasoline engines is very similar, especially when it comes to inline six engines.
Add to that SCR system and behind vehicle nothing reminds you of diesel. However, SCR system is expensive and too many parts that have to work in perfect harmony to achieve all that and it is problem. SCR is not problem to install on 18 wheeler since there is a lot of space, but personal vehicles are issue. Just loom issues BMW's, Audi's, MB's had with this system. It increases cost of diesel so much that completely negates its efficiency.
 
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Originally Posted By: Shannow
Originally Posted By: edyvw

Both So2 and NOx gases are contributing. You are right, SO2 is the worst when it comes to corrosion, but other gases are also an issue:
http://www.air-quality.org.uk/12.php
And that is what I said, with direct injection comes more NOx. Remember first GDI engine in Mitsubishi Carisma? Huge issue was ridiculously high NOx. The reason why other fallowed much later was problem of solving Nox.


No, it was Sox...NOx contributed to photochemical smog at ground level, along with lung iritation, and (for eg. power station emissions acid rain..again, nothing like SOx)

It's nothing to do with direct injection, it's the nature of having nitrogen and oxygen at 3.76:1 molar concentrations exposed to high heat...they react, in a fast forward, slow backward reaction and leave the engine as various oxides of nitrogen...it was the CR and lean combustion of diesels that did it.

GDI came along and mimicked it...in modern "Engines that burn Gasoline"

NOx was easy...drop the cobustion temperatures...EGR came in in the early '70s for gassers. Water injection could have done it too.

Yeah but if you drop combustion temperature what happens with consumption? Today when manufacturers use 0W16 oils to squeeze several drops of gasoline.
 
Originally Posted By: edyvw

Yeah but if you drop combustion temperature what happens with consumption? Today when manufacturers use 0W16 oils to squeeze several drops of gasoline.


Originally Posted By: edyvw

Well, no soot thanx to DPF.


That's my point exactly...you are taking 30 year old "proofs", applying them to today and then stating that if 30 years of advances were stripped off, we'd be where we are 30 years ago.

Your arguments are emotional and simply not rational.

(fogetting the NOx is lower in diesels and Nox dissolving buildings of course, they were simply statements made that were incorrect, but BELIEVED as fact from the get go)
 
Originally Posted By: edyvw

Yeah but if you drop combustion temperature what happens with consumption? Today when manufacturers use 0W16 oils to squeeze several drops of gasoline.


Given that I'm POSITIVE that you don't know the answer to your rhetorical question, I'll help you out.

BSFC is one way of representing thermal efficiency. Here's the BSFC effect of varying EGR rates on a (modern) diesel with single squirt and staged compbustion...not just how bad the effect of EGR is...oh wait.
10.5923.j.ijee.20120206.03_010.gif


Here's it expressed as thermal efficiency, shows the effect of engine friction at low loads on thermal efficincy, and again what happens with EGR.
10.5923.j.ijee.20120206.03_009.gif


Here's the change in (non building dissolving) NOx.
10.5923.j.ijee.20120206.03_016.gif



http://article.sapub.org/10.5923.j.ijee.20120206.03.html
 
Originally Posted By: Shannow
Originally Posted By: edyvw

Yeah but if you drop combustion temperature what happens with consumption? Today when manufacturers use 0W16 oils to squeeze several drops of gasoline.


Originally Posted By: edyvw

Well, no soot thanx to DPF.


That's my point exactly...you are taking 30 year old "proofs", applying them to today and then stating that if 30 years of advances were stripped off, we'd be where we are 30 years ago.

Your arguments are emotional and simply not rational.

(fogetting the NOx is lower in diesels and Nox dissolving buildings of course, they were simply statements made that were incorrect, but BELIEVED as fact from the get go)

I think you are purposely trying to twist my point. My argument is that DPF is improvement as well as SCR as well as before that was EGR, as well as CR etc. If we strip that off we get 1.6 diesel from Golf II or whatever. You know all that, highly doubt you did not understand that. Or you are just too fast to prove how smart you are. OK, we get that, you are.
I already posted link about SO2 (yes, SO2) and other elements including NOx and their corrosive effect. So, read it, do not read it, or just continue to patronize others.
I fully expect you will solve European emission problem the way this goes.
 
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