Ford's answers to the NHTSA 6.7 Investigation
There was a request for a link to Ford's answer's to the NHTSA investigation posted on a previous thread, since closed. Here is the link: Ford's NHTSA Answers to the 6.7 investigation This PDF i...
Forum Discussion
Time to throw in the towel on conventional Diesels?
Looking at how reducing combustion temperatures (to cut NOx emissions is causing lower and lower thermal gradients.
Is it time we give up on this and go the other way --- with high temperature (high thermal gradient) combustion, perhaps with adiabatic engines made of ceramics, jacking up the temperature as high as possible, then deal with the emissions after the fact?
If that is the strategy, it offers some odd ball ideas.
Doing some thinking about triple expansion 2 stroke.
Classic triple expansion feeds in steam, and is progressively cooled in different sized cylinders to extract the most heat from it.
We can mod the thing and have 3 different 2 strokes, each feeding off the exhaust gas of the other.
Combustion happen in Cylinder 1, then onto next cylinder.
Cylinder #1 can be extremely high temperature combustion that generates a lot of NOx, CO, SOx, etc. that have a very good thermal gradient, up to the limits of the materials and cooling.
The hot gases can then be fed into a second cylinder, where additional fuel is injected in a mix of exhaust gases (think massive EGR without the EGR) and then burned for a bit more work.
At this point, the still very hot mixture can be fed into a SCR to clean up the NOx, CO, SOx, and HC, and the still hot gases (without more fuel) power the last cylinder.
The gases, with little NOx, CO, SOx, and unburnt HC then does it last expansion before exhausting to a conventional turbo charger to extract a bit more heat.
Finally, head to DPF to do its thing, and any residual reduction.
Hypothesis: 2 different combustion cycles may reduce particulate formation if the temperature is high enough to cause the carbon particles from cylinder 1 to combust and burn.
It may be an idea to put the DPF in between Cylinder 1 and 2 and let it be trapped there and combust, leaving relatively little DP after Cylinder 2?
Or maybe even a DPF between Cylinder 2 and 3? and let the energy from combustion be scavanged by cylinder 3?
Hmmmmm...
Looking at how reducing combustion temperatures (to cut NOx emissions is causing lower and lower thermal gradients.
Is it time we give up on this and go the other way --- with high temperature (high thermal gradient) combustion, perhaps with adiabatic engines made of ceramics, jacking up the temperature as high as possible, then deal with the emissions after the fact?
If that is the strategy, it offers some odd ball ideas.
Doing some thinking about triple expansion 2 stroke.
Classic triple expansion feeds in steam, and is progressively cooled in different sized cylinders to extract the most heat from it.
We can mod the thing and have 3 different 2 strokes, each feeding off the exhaust gas of the other.
Combustion happen in Cylinder 1, then onto next cylinder.
Cylinder #1 can be extremely high temperature combustion that generates a lot of NOx, CO, SOx, etc. that have a very good thermal gradient, up to the limits of the materials and cooling.
The hot gases can then be fed into a second cylinder, where additional fuel is injected in a mix of exhaust gases (think massive EGR without the EGR) and then burned for a bit more work.
At this point, the still very hot mixture can be fed into a SCR to clean up the NOx, CO, SOx, and HC, and the still hot gases (without more fuel) power the last cylinder.
The gases, with little NOx, CO, SOx, and unburnt HC then does it last expansion before exhausting to a conventional turbo charger to extract a bit more heat.
Finally, head to DPF to do its thing, and any residual reduction.
Hypothesis: 2 different combustion cycles may reduce particulate formation if the temperature is high enough to cause the carbon particles from cylinder 1 to combust and burn.
It may be an idea to put the DPF in between Cylinder 1 and 2 and let it be trapped there and combust, leaving relatively little DP after Cylinder 2?
Or maybe even a DPF between Cylinder 2 and 3? and let the energy from combustion be scavanged by cylinder 3?
Hmmmmm...
