There has been a lot of discussion about the potential benefits of the upcoming Ingenium replacement for the current range of diesel power plants used in the DS. Much of this has focussed on the pros and cons of waiting for the new engines and the expected greater efficiency and lower emissions as compared to the well proven and refined over-time attributes of the current engines. Most of this debate is now irrelevant since it seems JLR are now taking orders for cars with the new engines, albeit accompanied by their well-proven vagueness and confusion as to whether these will be 2WD or 4WD and when they will be released etc. Suffice to say that I am very happy with my SD4 that so far (though since it is only days old I have reigned in my enthusiasm to try it too hard!) seems quiet, responsive and consistently delivering MPGs of 40+ on medium runs.
Not being an automotive engineer I have, however, wondered a little about some of the implications of the Ingenium engines. There seems to be few hard facts regarding how they will perform other than by extrapolating from their use in Jaguar cars. But we can expect that they will deliver better MPGs and the SD4 and clearly lower CO2 emissions - especially for 2WD versions.
In order to do this JLR have engineered in some sophisticated design to lower friction, adjust valve timings and lower weight. And, I understand that in the diesel engines the employ a mix of engine gas recirculation (EGF) and selective catalytic reduction (SCR) to lower NOx emissions. Both these technologies have been used for years on commercial vehicles and as well as on many cars.
SCR relies upon the continuous injection of a diesel emissions fluid (DEF - often referred to as 'AdBlue'). This is essentially a high purity aqueous Urea solution to helps to convert harmful gases during the combustion process. There do, though, seem to be some downsides to this. Leaving aside that whilst DEF is non-toxic in the normal sense, it is very harmful if spilt into waterways because it causes severe de-oygenation. It is also corrosive.
More significantly, it has to be kept topped up since the engine will essentially shut down into 'safe mode' if it runs too low. I believe that an engine consumes around 5% DEF compared to the volume of diesel burnt - so quite a lot over the course of a years driving. Although relatively cheap, it has to be bought and put into the car and, of course, held in a tank. I have heard nothing of how that will work. Will users be able to fill their own vehicles (as per VWs) or is this going to be a dealer-only task? How much will the DEF tank hold and where will it be? - it will, of course, offset to a small degree any engine weight reduction but perhaps more importantly will presumably take up space - say in the boot are or under the floor?
The technology demands a very accurate means of injecting measured amounts of fluid into the air/diesel mixture - no doubt this has been perfected during its use elsewhere but a potential source of more maintenance.
Euro6 is on its way and that must be good for the environment - and our health - but it seems to me that the hype surrounding its benefits is to an extent obscuring some aspects that are being given little exposure. This could simply be my own acknowledged ignorance but, if not, I think it would be helpful to have a little clarification.
Not being an automotive engineer I have, however, wondered a little about some of the implications of the Ingenium engines. There seems to be few hard facts regarding how they will perform other than by extrapolating from their use in Jaguar cars. But we can expect that they will deliver better MPGs and the SD4 and clearly lower CO2 emissions - especially for 2WD versions.
In order to do this JLR have engineered in some sophisticated design to lower friction, adjust valve timings and lower weight. And, I understand that in the diesel engines the employ a mix of engine gas recirculation (EGF) and selective catalytic reduction (SCR) to lower NOx emissions. Both these technologies have been used for years on commercial vehicles and as well as on many cars.
SCR relies upon the continuous injection of a diesel emissions fluid (DEF - often referred to as 'AdBlue'). This is essentially a high purity aqueous Urea solution to helps to convert harmful gases during the combustion process. There do, though, seem to be some downsides to this. Leaving aside that whilst DEF is non-toxic in the normal sense, it is very harmful if spilt into waterways because it causes severe de-oygenation. It is also corrosive.
More significantly, it has to be kept topped up since the engine will essentially shut down into 'safe mode' if it runs too low. I believe that an engine consumes around 5% DEF compared to the volume of diesel burnt - so quite a lot over the course of a years driving. Although relatively cheap, it has to be bought and put into the car and, of course, held in a tank. I have heard nothing of how that will work. Will users be able to fill their own vehicles (as per VWs) or is this going to be a dealer-only task? How much will the DEF tank hold and where will it be? - it will, of course, offset to a small degree any engine weight reduction but perhaps more importantly will presumably take up space - say in the boot are or under the floor?
The technology demands a very accurate means of injecting measured amounts of fluid into the air/diesel mixture - no doubt this has been perfected during its use elsewhere but a potential source of more maintenance.
Euro6 is on its way and that must be good for the environment - and our health - but it seems to me that the hype surrounding its benefits is to an extent obscuring some aspects that are being given little exposure. This could simply be my own acknowledged ignorance but, if not, I think it would be helpful to have a little clarification.
