Tier IV, Diesel emissions, and the Volkswagen scandal

[LensCapOn]

From what I can remember reading, GE is using very high pressure going to the injectors to get an extremely fine fuel spray. That was a key to reducing soot formation (with a possible efficiency gain). With less soot to begin with, exhaust gas recycling may work without the huge problems OTR trucking had with it. Since there is so much extra cooling on the incoming air, that may have also reduced NOx, which is formed at high combustion temperatures. Since a turbo can pack as much as needed into the engine GE may not need to violate the laws of physics and chemistry, as VDub did, to pass the emissions tests.

 

 

Time, and more EPA tests, will tell. (And we bring VW and Trains together. Yay!)

[M636C]

Certainly, MTU are claiming compliance with Tier 4 through very high pressure injection (which is said to provide finer atomisation and less formation of particulates). Temperature is also controlled by multiple injections timed to spread the combustion over a longer time thus reducing the peak temperature, hopefully below that temperature at which NOx is generated. The exhaust gas being recirculated goes through a second intercooler about the same size as the intake air intercooler, giving even more control of temperature, which with the multiple fuel injections does indeed control temperature better than previous designs.

One difference from VW is that every available technique is being used, while VW were much more concerned with minimising cost. Of course when your product sells for millions of dollars rather than thousands and is built in much smaller numbers, you have more leeway in selecting technical solutions.

I'm not saying that there will be big, unexpected problems since GE have been working on these for quite some time.  But how well all these innovations will work day to day over years remains to be seen.

M636C

[oltmannd]

M636C

So I don't believe that the very small performance improvement quoted was anything more than an invented reason to explain a new design of turbocharger which was intended to increase reliability without having to admit that there had been failures in the past. So why should we expect to hear about any problems with Tier 4? However, if some improvements to the Tier 4 engines are announced, it might be worth checking to see what was changed, since that might relate to problems not publically admitted...

I think they learned this behavior from EMD.

RR "We have a problem"

EMD "No, you don't"

RR "Yes, we do.  See?"

EMD "You must be doing something wrong."

RR "No, we're not.  Take a look."

EMD "Oh, that problem!   We already a fix in the works and are testing it on RRXYZ."

[JayPotter]

The second and third Tier 4 units delivered to CSX were sent directly to Grafton, West Virginia and placed in helper service on September 9th.  That assignment has the heaviest duty cycle on the railroad and is conducive to revealing problems in new locomotives.

[Wizlish]

oltmannd

M636C

So I don't believe that the very small performance improvement quoted was anything more than an invented reason to explain a new design of turbocharger which was intended to increase reliability without having to admit that there had been failures in the past. So why should we expect to hear about any problems with Tier 4? However, if some improvements to the Tier 4 engines are announced, it might be worth checking to see what was changed, since that might relate to problems not publically admitted...

 

 

I think they learned this behavior from EMD.

Who I have to suspect cribbed it from crApple, or else taught their current clowder of "geniuses" the finer points of invert customer servicing.

Does GE have a history of 'explaining away' disastrous engineering failures or shortcomings in this way?  I had thought their typical thing was clever whiz-bang solutions that did not work out right in the long run, or were compromised by being 'built to a price',  with little or no excuse made by them afterward...

[M636C]

JayPotter wrote the following post 8 hours ago:

The second and third Tier 4 units delivered to CSX were sent directly to Grafton, West Virginia and placed in helper service on September 9th.  That assignment has the heaviest duty cycle on the railroad and is conducive to revealing problems in new locomotives.

The CSX locomotives were ET44AH type and Grafton is their natural home. That is the best place for CSX and GE to test them. All I'm saying is that unless something goes spectacularly wrong, the rest of us won't get a running commentary on their strengths and particularly not on their weaknesses.

 

M636C

[Boyd]

JayPotter

The second and third Tier 4 units delivered to CSX were sent directly to Grafton, West Virginia and placed in helper service on September 9th.  That assignment has the heaviest duty cycle on the railroad and is conducive to revealing problems in new locomotives.

 

is there a break in period for new locomotives which doesn't include severe duty? Or are the engines ran several hours for break in at the factory?

[JayPotter]

I'm unfamiliar with pre-delivery procedures -- except that GE weighs locomotives before they are delivered to CSX -- however there are some problems that are only identified after locomotives have been operated for varying periods of time in various kinds of assignments.  For example, a problem that arises in high speed, low tractive effort service might not arise in high tractive effort low speed service. At least on CSX, locomotives that are intended for severe duty don't have a breaking-in period.  The two Tier 4 units that I mentioned were placed in service at Russell, Kentucky, routed DIT to Grafton, arrived there on September 6th and were placed in storage status, and were configured for testing on September 8th.  On September 9th, they were taken out of storage status and entered helper service. As far as I know, they're still shoving trains.  However because the adhesion-related systems that enable those units to do what they're doing were developed during a 15-year period, it would have been surprising if they hadn't performed as expected.  The next issue will be how well they perform during winter conditions.

[daveklepper]

[quote user="M636C"]

Certainly, MTU are claiming compliance with Tier 4 through very high pressure injection (which is said to provide finer atomisation and less formation of particulates). Temperature is also controlled by multiple injections timed to spread the combustion over a longer time thus reducing the peak temperature, hopefully below that temperature at which NOx is generated. The exhaust gas being recirculated goes through a second intercooler about the same size as the intake air intercooler, giving even more control of temperature, which with the multiple fuel injections does indeed control temperature better than previous designs.

One difference from VW is that every available technique is being used, while VW were much more concerned with minimising cost. Of course when your product sells for millions of dollars rather than thousands and is built in much smaller numbers, you have more leeway in selecting technical solutions.

I'm not saying that there will be big, unexpected problems since GE have been working on these for quite some time.  But how well all these innovations will work day to day over years remains to be seen.

M636C

 

[END quote]

Here is something from Physics Today website on the VW issue:

The recent admission by Volkswagen that it equipped diesel cars with "defeat devices" has remained on the front and home pages of news outlets for days. Yet despite the mass of coverage, details on exactly how the devices cheated on emissions tests for nitrogen oxides have been sketchy and sometimes contradictory.

Most outlets reported that the device activated emissions-reduction technology only when it sensed the car was being tested. When the device sensed the car was out on the road, it deactivated the technology, which would have lowered the cars' performance and fuel economy.

But those same reports typically omitted to say which of several different emissions-reduction technologies are installed in the VW cars. Also missing were explanations of why diesels belch nitrogen oxides in the first place. Curious to discover the answers, I decided to investigate.

Diesels, turbines, and other heat engines convert thermal energy into mechanical energy. The higher the engine's operating temperature, the greater its efficiency is. Knowing that basic principle of thermodynamics, Rudolf Diesel sought in the 1890s to develop an internal combustion engine that ignited fuel by injecting it into hot, compressed air.

After experimenting with coal dust and vegetable oils as fuels, Diesel settled on a crude oil extract. What we now call diesel is made up of hydrocarbons that have between 10 and 15 carbon atoms per molecule. Gasoline, which is made up of molecules with 4 to 12 carbons, has the higher energy density per unit mass. But diesel, being denser, has the higher energy density per unit volume—which is what counts when it comes to filling up a fuel tank.

A two-door Borgward Hansa 1800. I can't tell whether this example has a gasoline or diesel engine.

When tested in 1954 by the British car magazine The Motor, the diesel version of Germany's Borgward Hansa 1800 turned out to consume diesel at a rate of 45.6 miles per imperial gallon (38.0 miles per US gallon). A year later The Motor tested a comparable gasoline-powered car, Britain's Austin Cambridge A50. It managed 28.0 miles per imperial gallon (23.3 miles per US gallon). Diesel engines retain their efficiency edge to this day. Indeed, low-speed marine diesel engines are the most fuel-efficient of any internal combustion engines.

The difference in the molecular mass of their respective fuels dictates how diesel and gasoline engines operate. Gasoline, being more volatile than diesel, more readily forms a mist of explosive droplets. When mixed with air, the droplets can be ignited with a spark from an electric discharge.

Diesel's lower volatility requires a different ignition mechanism. Air is drawn into the cylinder by the retracting piston. When the piston reverses direction, it compresses the air, thereby heating it. At the top of the compression stroke, droplets of diesel fuel are injected into the cylinder. The hot compressed air further vaporizes the fuel and ignites it. The resulting explosion drives down the piston.

The amount of oxygen sucked into the cylinder during the intake stroke is more than enough to burn the diesel. At the high temperatures and pressures reached during the power stroke, oxygen reacts with nitrogen to form nitrogen oxides. The same reactions take place in gasoline engines, but at much lower rates. That's because the gasoline and air are mixed before they are injected into the cylinder. The ratio of gasoline to air is adjusted to ensure that most of the available oxygen is consumed by combustion, rather than by the production of nitrogen oxides.

Nitrogen oxides released into the atmosphere react with sunlight to produce ozone, a potent pollutant. One way to reduce nitrogen oxide emissions from diesel engines is to convert the oxides in the exhaust back into nitrogen and oxygen. Selective non-catalytic reduction (SNCR) achieves that goal by passing the exhaust gas through an aqueous solution of urea known generically as diesel exhaust fuel (DEF) and sold commercially as AdBlue.

Because the removal of nitrogen oxides with DEF takes place after combustion, it does not affect the engine's performance. However, the car's AdBlue tank must be periodically replenished. According to BMW, whose diesel cars are equipped with SNCR, one tank of AdBlue will last about 15 000 km (9400 miles).

Exhaust gas recirculation

Circumventing SNCR would reduce a car's consumption of AdBlue, but it would boost neither its performance nor its fuel economy. The technology that Volkswagen used to reduce nitrogen oxide emissions during tests is a different one known as exhaust gas recirculation (EGR).

Diesel exhaust is made up mostly of carbon dioxide and water vapor. Feeding cooled exhaust gas back into the cylinder reduces the production of nitrogen oxides in two ways: By displacing oxygen, it deprives nitrogen of its partner in the reactions that form nitrogen oxides; by lowering the temperature, it reduces the reactions' efficiency.

Displacing oxygen also reduces the efficiency of combustion, which both lowers the engine's efficiency and leads to the emission of more soot and carbon monoxide. And in lowering the temperature, EGR reduces engine efficiency further. The additional soot can be removed with filters, but the lost efficiency cannot be recovered.

Most of the reports I've read about the Volkswagen emissions scandal have highlighted the software that switched the EGR on and off. But software is impotent without hardware. To recognize when a car was being tested and not driven, the defeat device required data from a range of sensors—sensors that a noncheating car might not need. The defeat device also requires the physical means to control the EGR system.

I mention hardware because it widens the scope of the Volkswagen conspiracy. Whereas it's conceivable that a single software engineer, directed by a single manager, could have secretly written and uploaded the code that ran the defeat device, installing its associated hardware would require a larger and more diverse team of conspirators. Additional parts might be needed.

My friend Neil runs a chain of auto repair shops in Maryland and Virginia. When I asked him about the scandal, he recalled that one of his mechanics had removed the EGR system from his own VW car. Instructions for doing that can be found on YouTube. ראש הטופס

תחתית הטופס

 

[oltmannd]

Wizlish

 

 

oltmannd

M636C

So I don't believe that the very small performance improvement quoted was anything more than an invented reason to explain a new design of turbocharger which was intended to increase reliability without having to admit that there had been failures in the past. So why should we expect to hear about any problems with Tier 4? However, if some improvements to the Tier 4 engines are announced, it might be worth checking to see what was changed, since that might relate to problems not publically admitted...

 

 

I think they learned this behavior from EMD.

 

 

Who I have to suspect cribbed it from crApple, or else taught their current clowder of "geniuses" the finer points of invert customer servicing.

 

My familiarity with EMD was from the late 70s, early 80s.  Market dominence extinguishes humility....

[erikem]

M636C

Certainly, MTU are claiming compliance with Tier 4 through very high pressure injection (which is said to provide finer atomisation and less formation of particulates). Temperature is also controlled by multiple injections timed to spread the combustion over a longer time thus reducing the peak temperature, hopefully below that temperature at which NOx is generated. The exhaust gas being recirculated goes through a second intercooler about the same size as the intake air intercooler, giving even more control of temperature, which with the multiple fuel injections does indeed control temperature better than previous designs.

A thought came to mind that may be a bit too far out in left field...

I wonder if injecting water towards the end of the fuel injection process might help reduce NOx and still maintain efficiency? This would be similar to the approach of injecting steam into combustion turbines, where it reduced both SFC and NOx (the former by acting a bit like a poor man's combined cycle plant). In a dismal -er- diesel engine, the increased mass in the cylinder may compensate for the lower peak temperatures.

A couple of issues: One is getting the timing right to not interfere with the complete combustion of the fuel. The other is the logistics of the water tank.

 - Erik

[Wizlish]

erikem

A thought came to mind that may be a bit too far out in left field...

Not as strange as you think - I knew of at least  two examples of Snow  'methanol injection' systems on light diesel engines (Cummins 6BT) that had the effect of limiting EGT by doing some control of peak combustion temperature.  This is not of course the same thing as 'pilot injection of water' (which is what I understood your idea to involve, with a complete second common-rail high-pressure system just for the water/alcohol mix) but I would agree that in conjunction with a different modulation of the fuel injection (and some adjustment of variable cam activity) having the water/alcohol in the intake charge would have some effect in reducing heat-catalyzed NOx levels

The situation is a bit different in a gas turbine as the steam injection can be continuous, and water injection can be modulated with simple  "PWM" where injection timing of the individual pulses is not critical.  In a diesel engine, you need both very precise timing and  mass-metering of the water charge, and then good turbulent mixing within a probably-nondeterministic combustion plume. 

The great and immediate problem I see with NOx reduction via direct water injection is that you will be trading off between NOx and nanoparticulate generation.  A great part of the latter is the result of slightly early quench of combustion reactions, either by local lack of stoich oxygen coupled with subsequent net-reducing conditions in the plume until the gas temperature is below critical temperature for the carbon-oxygen reaction, or due to other quench of the carbon reaction.  In my opinion nanoparticulates are a SUBSTANTIALLY greater health risk than a couple of tenths-percent reduction in emitted NOx levels.

I am hoping that 'Entropy' (from Cat) will chime in with some comments, as he has already provided some eye-opening insights on practical NOx reduction  in high-speed diesel practice.

[erikem]

Wizlish

 The great and immediate problem I see with NOx reduction via direct water injection is that you will be trading off between NOx and nanoparticulate generation.  A great part of the latter is the result of slightly early quench of combustion reactions, either by local lack of stoich oxygen coupled with subsequent net-reducing conditions in the plume until the gas temperature is below critical temperature for the carbon-oxygen reaction, or due to other quench of the carbon reaction.  In my opinion nanoparticulates are a SUBSTANTIALLY greater health risk than a couple of tenths-percent reduction in emitted NOx levels.

That's something that I was wondering about as well, there might be a sweet spot where the water is injected near the end of the combustion process to reduce the time that the air spends above the critial point for NOx generation. This would depend on whether NOx production reaches equilibrium almost instantaneously or if the reaction rate is slow enough such that equilibrium is not attained.

Nanoparticles would be a worry - which brings me to goig off on another tangent... My understanding is the soot production is from part of the combustion process where acetylene is formed during the breaking of C-C and C-H bonds. One proposed clean diesel fuel is di-methyl ether and I wonder if the lack of C-C bonds would eliminate soot production?

 

[guetem1]

BNSF appears highly enamoured with the GE ET44C4 (4400 hp 4 traction motors)  thus far they appear to be running well, as I have yet to encounter a breakdown on my RR anyway.  Although we did have some issues when one was assigned to a crude by rail train and it promptly laid down on a hill (that 4 vs. 6 traction motor thing....)

[Wizlish]

erikem

Nanoparticles would be a worry - which brings me to going off on another tangent... My understanding is the soot production is from part of the combustion process where acetylene is formed during the breaking of C-C and C-H bonds. One proposed clean diesel fuel is di-methyl ether and I wonder if the lack of C-C bonds would eliminate soot production?

Iam not sure I understand how large quantities of triple-bonded carbon could ever form in combustion of typical diesel fuel.  My admittedly non-engineering understanding is that the soot production is related to fuel-droplet size and the changes in composition of the carbon backbones as the hydrogens are more easily 'combusted off' at the necessarily short reaction times posed by higher-speed engine operation.  This would lead to prediction that finer atomization of the liquid fuel during injection (and subsequent preservation of separation of the finely-atomized particled, e.g. by electrostatic charge) would result in less nanoparticulate generation, and I believe that is observed in practice

DME is an excellent additive to diesel fuel (I believe it is a good promoter, and is oxygenated to boot) but I understand its density, vapor pressure, and to an extent production cost make it unlikely as a replacement for fossil diesel, and perhaps for biodiesel.  It is certainly attractive as a fuel for some uses!

On the other hand, I would like to see more published research into the characteristics of promoters in modern high-speed diesel engine combustion.  It took me a while to track down the reasons why small traces of toluene in some older engine designs (mostly IDI engines if I remember correctly) produced better results but larger (still 'trace' level) quantities did not.  I would be tempted to consider whether a 'water injection' system with the characteristics you were describing might be used for selective injection of promoters at appropriate times (one of those times being in advance of TDC, at the time current pilot injection may be introducing small charges of fuel to generate promoters facilitating quicker reaction of the main injection charges).  You might then see some selective recombination from the increasing dissociation of water above 800 degrees during the hotter parts of actual main-charge combustion (although I think you would still see selective recombination with hydrogen rather than carbon in most cases).

BTW, I think most of the practical effect of "Brown's gas" and those other water-burning systems with the multiple driveshaft alternators and so forth are to generate better promoters, thereby increasing practical combustion efficiency (by which I mean the ability of the engine to convert piston pressure into usable crankshaft torque.)  Alternatively, anything that 'smooths' combustion or temperature risetime, without limiting reasonably complete combustion in the short time available during the operative part of the power stroke, has the potential to reduce many stresses on the engine, such as peak or reversing stresses in the crankshaft, and increase at least the perception of output power

[erikem]

The comment about acetylene being produced in a diesel engine was from GM ad in Scientific American circa 1980. GM ran one page ads in Sci Am describing some of the findings from their research department. I'm not sure of what the mechanism is for producing acetylene, but seeing how much acetylene torches smoke before the oxygen is turned on...

 - Erik

P.S. My fave acetylene "compound" is acetylozone, chemical formula HOOOCCH.

[Wizlish]

erikem

P.S. My fave acetylene "compound" is acetylozone, chemical formula HOOOCCH.

Especially when polymerized for use in monopropellant grains as PAO.  But things go still better with FLOX, as Mr. Herbert noted back in the day (presumably FLOX-30 and UDMH with so much oxidative potential already  in the fuel).  I do agree with retro's adoption of O15 (and, perhaps, C14 and tritium in the acetylene) to add a little sizzle to the proceedings...  :-O

Amusingly enough, my father and a couple of college friends worked on a mixture of cryogenic acetylene and ozone for "certain uses" (emphatically not  controlled thrust!)   Supposedly, under some circumstances, propagation of effective "combustion" initiation was at a fair percentage of lightspeed.  What a pity that it was somewhat stochastically unstable even when microencapsulated with acetone...

Try as I might, I don't have a good railroad-related use for acetylozone technology. If there is an application of pulse detonation gas generation to free-turbine generation, you could among other things provide plenty of room in the hood for things like particulate filter or mufflers  ... but looking at how noise caused problems for straight free-piston generators, I tremble (perhaps literally at 30Hz!) to think how large a muffler might be required to satisfy the NSW authorities.

[M636C]

Clearly I must say something to Wizlish's post:

I would expect that to meet Australian domestic noise standards his pulse detonation free piston locomotive would end up looking a bit like the Belgian 1930s Franco Crosti locomotive but with twin mufflers carried on powered units articulated fore and aft of a central unit in which the pulse generator was (very) flexibly mounted.

Also in Australia, Volkswagen have announced that they will remove the standards avoidance software from their affected diesel engines. The sad part is that they don't need to, since there are no emission standards to exceed. Ford openly admit that their Australian market diesel cars don't meet Euro standards, in order to keep the price down (no particulate filter, for example) so why do Australian Volkswagen owners have to get reduced performance just to meet non applicable standards?

M636C

[BaltACD]

M636C

 

Also in Australia, Volkswagen have announced that they will remove the standards avoidance software from their affected diesel engines. The sad part is that they don't need to, since there are no emission standards to exceed. Ford openly admit that their Australian market diesel cars don't meet Euro standards, in order to keep the price down (no particulate filter, for example) so why do Australian Volkswagen owners have to get reduced performance just to meet non applicable standards?

M636C

 

Because VW has created a World Wide black eye situation - no matter if the individual countries have any sort of emissions regulations.  VW now feels they have to go 'above & beyond' to make ammends.

[erikem]

Wizlish

 Especially when polymerized for use in monopropellant grains as PAO.  But things go still better with FLOX, as Mr. Herbert noted back in the day (presumably FLOX-30 and UDMH with so much oxidative potential already  in the fuel).  I do agree with retro's adoption of O15 (and, perhaps, C14 and tritium in the acetylene) to add a little sizzle to the proceedings...  :-O

I ran across the HOOOCCH page 10 year ago after seeing Herr Herbert posting on one of the sci.space newsgroups. I was laughing so hard that my then 6 year old son wanted to see what was so funny. Need to look it up sometime as he now has enough chem background and a warped enough sense of humor to appreciate it.

I have run across something that makes FLOX benign by comparison - ClF3. One source said it was hypergolic with everything, metals, furniture, techinicians... Another source mentions that sand will burn in ClF3 and went on to tell about a ton of the stuff being made in the 1950's with a subsequent spill of said ton. The description was reminiscent of the corrosive good from "Alien".

Pulse detonation: back in the 60's a model airplane club had a fly in with four of the members bringing planes powered by the DynaJet Redheads. After many attempts, they got all four flying at once and the club had to lay low for several months afterwards due to complaints about the noise. OTOH, I would think that a turbine would provide some muffling...

 - Erik

[Entropy]

Boyd

If the car has a built in GPS it could tell that it's stationary, but in drive spinning the tires at 30mph. Or if just the drive tires are spinning and the other two aren't, the wheel speed sensors reading would tell the computer that we are being tested or we are stuck in a snow bank in St.Paul Mn. 

 

 

You're close, a private run investigation found when running a front wheel drive TDI Jetta/beetle/A3 on the dyno as done with an EPA test, the front wheels are run up to speed, rear wheels are stopped and the ABS light comes on, you don't get a choice. The meassured torque dropped 35 ft/lbs across the board, only 2hp drop. Then placed onto a four wheel driven dyno connecting all the rollers, four wheels spinning at the same speed, all the power came back.

So yes, ABS light on.... low nox setting... easy to program that.

[nfotis]

erikem

I ran across the HOOOCCH page 10 year ago after seeing Herr Herbert posting on one of the sci.space newsgroups. I was laughing so hard that my then 6 year old son wanted to see what was so funny. Need to look it up sometime as he now has enough chem background and a warped enough sense of humor to appreciate it.

I have run across something that makes FLOX benign by comparison - ClF3. One source said it was hypergolic with everything, metals, furniture, techinicians... Another source mentions that sand will burn in ClF3 and went on to tell about a ton of the stuff being made in the 1950's with a subsequent spill of said ton. The description was reminiscent of the corrosive good from "Alien".

 

Maybe you know about FOOF?

https://en.wikipedia.org/wiki/Dioxygen_difluoride

Cheers,

N.F.

[erikem]

nfotis

Maybe you know about FOOF?

Isn't that the stuff that's used to fill the "buffer" tank cars on a crude oil unit train, especially when hauling untreated Bakken crude????

From what I've heard, ClF3 is worse than FOOF and would not want to be within miles of a tankcar loaded with it.

[nfotis]

Well, it has been called "Satan's Kimchi", so this should give you an idea...

http://www.napavalley.edu/people/sfawl/Documents/Things%20I%20Won't%20Work%20With.pdf

N.F.

[Electroliner 1935]

oltmannd

I think they learned this behavior from EMD. RR "We have a problem" EMD "No, you don't" RR "Yes, we do.  See?" EMD "You must be doing something wrong." RR "No, we're not.  Take a look." EMD "Oh, that problem!   We already a fix in the works and are testing it on RRXYZ."

Sounds like the responses we (an electic utility with a large amount of communications circuits) used to get from (TPC) The Phone Company. (Remember the movie "The Presidents Analyst") You have to be like a dog owner and rub their noses in it. You get the response that "nobody else has reported that issue" After a lot of "escalation and frustration, you get someone who knows what more should have known and the problem gets cured. Until the next time. 

[Wizlish]

nfotis

Well, it has been called "Satan's Kimchi" ...

Not quite.  Satan's kimchi is the organosulfur stuff you can generate using FOOF.  Read the TIW3 section a bit further down about fun with thioacetone and its Appalachian cousins for a bit more on the 'kimchi' part.

Me, I'm still looking at that 433 exotherm.  Is the net reaction with water (the "H2S analog one up in the periodic table") anywhere near that energetic?  I apologize, but not that much, that I have neither the tools nor the inclination to find out in the chem lab...

[M636C]

To get a bit further back on topic...

http://www.marinelink.com/news/volkswagens-engine-claims399672.aspx

 

to summarise:

 

"In 2013, an Augsburg court fined MAN 8.2 million euros for violating laws with the misleading test results of dozens of marine diesel engines, including those sold to Skaugen. Software in the factory computers allowed displays to show lower fuel consumption than in reality, the court said".

 

VW are a majority owner of MAN.

 

MAN did build locomotive engines from the 1930s to the 1960s, but their last engine, the V6V 23/23 was taken over by MTU as their model MA 956. It was enlarged to become the model 1163  (which was close in dimensions to the EMD 710 but was of course four stroke). The 1163 is available for marine use meeting IMO Tier III, tougher than EPA Tier 4 but only with aftertreatment.

 

These engines being discussed regarding fuel consumption are bigger than locomotive engines. But this problem preceded the VW car revelations.

 

M636C