AHC: reduce 1930s-1940s German need for petrol
- Thread starter tomo pauk
- Start date
Tomo,
A whole series of interesting tradeoffs were available by the mid thirties, to reduce the need for gasoline in surface propulsion. Just as high performance gasoline engines require high mechanical compression, and therefore the knock resistance of relatively highly refined gasoline, pure Diesel engines are fussy about the fuel oil supplied. Here the ignition characteristics, or cetane number of the fuel, as well as its lubricity (in the injection system) are critical to performance and reasonable longevity. In both cases, the percentage of feedstock winding up as usable fuel is relatively small.
A range of modifications to the basic Diesel cycle would permit use of much less critical fuel and substantially lighter engine construction at the cost of some reduction in thermal efficiency. These range from the the early Hesselmann engine (a direct injection multi-fuel spark ignited engine) thru a range of precombustion Diesels, employing L'Orange and, later, Ricardo Comet chambers, fitted with glo plug or sparkplug igniters. The injectors would be much more robust and less critical than those necessary for pure Diesels and Cetane rating control would be unnecessary.
If water supply could be relied on, reciprocating steam (including as much condensing as practical) would be my choice despite its relatively low efficiency, since powdered coal (delivered by stoker screw to a high pressure blower and the burner in the flashtube boiler) would eliminate any petroleum requirement. I understand that there was a major project in the mid fifties, involving Convair in the development of a steam system for tank propulsion.
Dynasoar
A whole series of interesting tradeoffs were available by the mid thirties, to reduce the need for gasoline in surface propulsion. Just as high performance gasoline engines require high mechanical compression, and therefore the knock resistance of relatively highly refined gasoline, pure Diesel engines are fussy about the fuel oil supplied. Here the ignition characteristics, or cetane number of the fuel, as well as its lubricity (in the injection system) are critical to performance and reasonable longevity. In both cases, the percentage of feedstock winding up as usable fuel is relatively small.
A range of modifications to the basic Diesel cycle would permit use of much less critical fuel and substantially lighter engine construction at the cost of some reduction in thermal efficiency. These range from the the early Hesselmann engine (a direct injection multi-fuel spark ignited engine) thru a range of precombustion Diesels, employing L'Orange and, later, Ricardo Comet chambers, fitted with glo plug or sparkplug igniters. The injectors would be much more robust and less critical than those necessary for pure Diesels and Cetane rating control would be unnecessary.
If water supply could be relied on, reciprocating steam (including as much condensing as practical) would be my choice despite its relatively low efficiency, since powdered coal (delivered by stoker screw to a high pressure blower and the burner in the flashtube boiler) would eliminate any petroleum requirement. I understand that there was a major project in the mid fifties, involving Convair in the development of a steam system for tank propulsion.
Dynasoar
TruthfulPanda
Gone Fishin'
Booze.
Use E25 (75% gasoline - 25% alcohol). Even if fuel consumption is a mite higher, 20% savings on gasoline.
Use E25 (75% gasoline - 25% alcohol). Even if fuel consumption is a mite higher, 20% savings on gasoline.
TruthfulPanda
Gone Fishin'
Diesel:
1 - heavier engine - con
2 - lower fuel consumption - pro
3 - uses a different part of oil refinement outcome than gasoline - pro
Hence, diesel can be used alongside gasoline, cannot replace it
1 - heavier engine - con
2 - lower fuel consumption - pro
3 - uses a different part of oil refinement outcome than gasoline - pro
Hence, diesel can be used alongside gasoline, cannot replace it
marathag
Banned
Though low efficiency, you can also goto spark distillate engines, that was in that fuel oil/kerosene range, of around 30 octane. Many '20-30s US Tractors had engines that would run on that, but typically would start on gasoline for easier startup, then switch fuel after a few minutes when that distillate would properly atomize from the heat of the warm engine. Typically 4.75:1 CR vs 6:1 for gasoline.
marathag
Banned
For Straight Run distilling, that's true. But in the '30s they were starting to steam crack and hydrocrack the base crude. The latter process was developed in Germany, but was used more in the US to get more gasoline per unit of crude.
https://en.wikipedia.org/wiki/Gas_engine
The problem is the minituarization and not the availability of fuel, imho.
The problem is the minituarization and not the availability of fuel, imho.
thaddeus
Donor
https://en.wikipedia.org/wiki/Wood_gas ... maybe tanks would not be first choice of vehicles to convert
believe for navy at least the smaller ships needed to be coal fired (not including the S-Boats)
You might also substitute wood shavings or "wood oil" (a liquid derived from it; what it's correctly called, I don't recall
), both produced by pulp &/or paper plants. There's also industrial methanol, tho IIRC, that requires petroleum to produce...If you're willing to go further afield than even steam, there's the Stirling engine , which can also use powdered coal, wood chips, low grade petroleum (including bunker), or wood (like a fireplace...), with the added benefit of being shiny & new, appealing to Hitler's passion for anything never done before.
That's going to obstruct field of fire over the rear deck, y'know...
I was gonna roll with .. horses.. lots of horses
but wood fire would be cool as well.
Honestly any mechanized military is going to need petrol. the best way to relieve the dependence is to become independent of it, which is an oxymoron if you want a modern military.
so to that end. spend less on gas guzzlers and heavy equipment that will consume more oil/petrol. secure oil production, make friends, good friends with oil. Don't decide to go fight wars and take over the world without a high limit gas station credit card
Have somebody high up in the German power structure do the math and find out that in the event of a war oil would be a major weakness for Germany.
Research is put into getting engines to be more efficient, little if any research was done on that in the 1930s.
Research is put into getting engines to be more efficient, little if any research was done on that in the 1930s.
phx,
Whenever I hear anyone suggest a Stirling engine of more than about one horsepower, I (to use a quote from Hermann Goring) reach for my revolver! Between 2000 and 2003 I commuted between LA and Athens, Ohio (location of Ohio University) as senior consultant on a joint Department of Energy/ Corporate program to develop a biomass fueled free piston Sterling alternator. Meet all objectives? All but cost! -which rendered the project impractical for its intended purpose.
Stirling engine performance requires heat transfer thru a surface to heat and cool an enclosed working fluid (in this example helium at around 40 atm). The square/cube law reduces the integral surface area thru which heat is transferred relative to the internal volume, as cylinder size is increased. Great possibilities for very small (chip size) machines- an impractical stunt for large ones ( Yes, I know about Swedish Stirling Submarines). When cylinder size requires external tubing bundles for heat transfer, cost goes out the window!
Dynasoar
If you're willing to go further afield than even steam, there's the Stirling engine , which can also use powdered coal, wood chips, low grade petroleum (including bunker), or wood (like a fireplace...), with the added benefit of being shiny & new, appealing to Hitler's passion for anything never done before.
Whenever I hear anyone suggest a Stirling engine of more than about one horsepower, I (to use a quote from Hermann Goring) reach for my revolver! Between 2000 and 2003 I commuted between LA and Athens, Ohio (location of Ohio University) as senior consultant on a joint Department of Energy/ Corporate program to develop a biomass fueled free piston Sterling alternator. Meet all objectives? All but cost! -which rendered the project impractical for its intended purpose.
Stirling engine performance requires heat transfer thru a surface to heat and cool an enclosed working fluid (in this example helium at around 40 atm). The square/cube law reduces the integral surface area thru which heat is transferred relative to the internal volume, as cylinder size is increased. Great possibilities for very small (chip size) machines- an impractical stunt for large ones ( Yes, I know about Swedish Stirling Submarines). When cylinder size requires external tubing bundles for heat transfer, cost goes out the window!
Dynasoar
Horses was my first thought too, but I went with wood because I thought it would be cooler.I was gonna roll with .. horses.. lots of horses
but wood fire would be cool as well.
Honestly any mechanized military is going to need petrol. the best way to relieve the dependence is to become independent of it, which is an oxymoron if you want a modern military.
so to that end. spend less on gas guzzlers and heavy equipment that will consume more oil/petrol. secure oil production, make friends, good friends with oil. Don't decide to go fight wars and take over the world without a high limit gas station credit card
Keeping oil trade routes open is a good idea too, but of course the problem is that here is who makes oil in 1940:
1. United States - 183 million barrels
2. Soviet Union - 30 million barrels
3. Venezuela - 27 million barrels
4. Iran - 10 million barrels
5. Dutch East Indies - 8 million barrels
6. Mexico - 7 million barrels
7. Romania - 6 million barrels
I don't see a lot of friends of Germany on that list. And it goes down fast after that.
http://digital.library.northwestern.edu/league/le0280ah.pdf, p. 6.
Hence why I'm increasingly wondering if this notion of tripling German vehicle production is actually a realistic proposition.
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If oil is a major weakness for Germany, then simplifying vehicle production so you can have more tanks just makes the problem worse. Getting rid of tanks .... Well, you can't. Relying on horses... They already do. I think they're stuck. Whatever efficiencies you can play around with in engine design will at best only affect new manufacturing, introduce a whole host of new logistics and maintenance problems to do with servicing yet more types of engines in the field, and even then will only be shaving off consumption around the margins.
And with the numbers I just put in my post above this one, it's clear that there isn't exactly an easy route out of the oil problem for Germany strategically. The only obvious route I can see is to invade the Soviet Union.
Here's a bright idea for free: don't start wars with enemies who make almost all of the world's supply of a strategic resource you need to fuel your war machine.
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