Steam Powered BMW

[Alastor]

BMW unveils the turbosteamer concept

December 14, 2005 A large percentage of the energy released when petroleum is burned disappears out the exhaust system as heat. This has always been the case but the amount of energy released looks set to be cut by more than 80% thanks to a new system devised by BMW. BMW’s announcement of the new technology is somewhat of a technological bombshell as it adds yet another form of hybrid automobile – a turbosteamer.

The concept uses energy from the exhaust gasses of the traditional Internal Combustion Engine (ICE) to power a steam engine which also contributes power to the automobile – an overall 15 per cent improvement for the combined drive system. Even bigger news is that the drive has been designed so that it can be installed in existing model series – meaning that every model in the BMW range could become 15% more efficient overnight if the company chose to make the reduced consumption accessible to as many people as possible.

Combining the innovative assistance drive with a 1.8 litre BMW four-cylinder engine on the test rig reduced consumption by up to 15 percent and generated 10 kilowatts more power and 20 Nm more torque. This increased power and efficiency comes for, well, … nothing. The energy is extracted exclusively from the heat in the exhaust gases and cooling water so it is essentially a quantum leap in efficiency.

The Turbosteamer is based on the same principle of the steam engine: liquid is heated to form steam in two circuits and this is used to power the engine. The primary energy supplier is the high-temperature circuit which uses exhaust heat from the internal combustion engine as an energy source via heat exchangers. More than 80 percent of the heat energy contained in the exhaust gases is recycled using this technology. The steam is then conducted directly into an expansion unit linked to the crankshaft of the internal combustion engine. Most of the remaining residual heat is absorbed by the cooling circuit of the engine, which acts as the second energy supply for the Turbosteamer.

The development of the assistance drive has reached the phase involving comprehensive tests on the test rig. The components for this drive have been designed so that they are capable of being installed in existing model series. Tests have been carried out on a number of sample packages to ensure that the BMW 3 Series provides adequate space. The engine compartment of a four-cylinder model offers enough space to allow the expansion units to be accommodated.

Ongoing development of the concept is focusing initially on making the components simpler and smaller. The long-term development goal is to have a system capable of volume production within ten years.

LINK: http://www.gizmag.com/go/4936/

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Over the next decade it will be interesting to see how this technology fairs against other alternative power sources.

[henk4]

to make it perfectly clear, the steam will not generate both a 15% efficiency increae and a 15% increase in power at the same time. You only get one of the two....

[hightower99]

This system seems rather ineffecient to me as roughly 60% of the total thermal energy from the gas that goes in comes out in the exaust and they claim that they can get 80% of that so roughly 48% of the thermal energy is reclaimed. From that they seem to make only 15% more power and/or 15% more mileage!!! now assuming the engine runs at 30% and 10% is lost to the surrounding air and 60% goes out the exaust then the steam engines get more energy than the IC engine but only contribute 15%!!! this doesn't sound like such a great solution.

A well made turbo could do the same! and it would weigh less!

[Matra et Alpine]

A well made turbo could do the same! and it would weigh less!

and then STILL there is plenty of heat in the exhaust gasses to add a steam engine SO they can still apply it and get even more !!!

A good steam engine can extract MASSIVE amounts of eeh latent energy, especlaly if combined with a partial vacuum exhaust extraction and triple exapansion chamber. On of those amazing facts about the Scottish buitl triple expansion steamship -- one sheet of paper provide the energy necessary to move one TON of goods one MILE. WHen you look at it that way, it's pretty impressive what can be achieved with a good engine. Getting it to scale down will be fun

and re your calculations. Remember that they are extracting the energy from the WASTED/LOST energy of the IC engine - which aren't all that efficient.

[Alastor]

This system seems rather ineffecient to me as roughly 60% of the total thermal energy from the gas that goes in comes out in the exaust and they claim that they can get 80% of that so roughly 48% of the thermal energy is reclaimed. From that they seem to make only 15% more power and/or 15% more mileage!!! now assuming the engine runs at 30% and 10% is lost to the surrounding air and 60% goes out the exaust then the steam engines get more energy than the IC engine but only contribute 15%!!! this doesn't sound like such a great solution.

A well made turbo could do the same! and it would weigh less!

Generally, it is considered that about 30% of the thermal energy produced from the fuel is lost in the exhaust. While another 30% is lost to the cooling system. The article says that 80% of the energy in the exhaust is recovered with the steam engine (presumable a turbine).

So at best it would be 80% of 30% which is a total of 24%, but I suspect that doesn’t include the turbine losses. Assuming that is the case then 15% / 24% implies a turbine efficiency of 62.5 %, which seems low but plausible. However, this is just speculation as the article does not define how these were obtained.

[PerfAdv]

This is great news!! What's not to like about getting more out of what is put in?

[hightower99]

Generally, it is considered that about 30% of the thermal energy produced from the fuel is lost in the exhaust. While another 30% is lost to the cooling system. The article says that 80% of the energy in the exhaust is recovered with the steam engine (presumable a turbine).

So at best it would be 80% of 30% which is a total of 24%, but I suspect that doesn’t include the turbine losses. Assuming that is the case then 15% / 24% implies a turbine efficiency of 62.5 %, which seems low but plausible. However, this is just speculation as the article does not define how these were obtained.

what is the colour of the sky in your world???

actually in reality it is assumed that the engine extracts 30% to make mechanical power(this is not at the wheels this is in the cylinder) then roughly 50-60% rushes out of the exaust and 10-20% is absorbed by the walls and cooling system. to take a closer look that 50-60% that goes out the exaust gets even lower the second it leaves the head losing about 10% to the surrounding atmosphere (for a double walled exaust this number goes down to about 1%) of the 10-20% that is absobed by the walls and cooling system between 30-50%(depending on thermostat setting) of this goes through the metal and out into the surrounding air without going through the cooling system the cooling system grabs 50-70% of the heat and uses the radiator to dump that into the air. so my equation stands the steam engine gets about 48% of the total thermal energy (actually slightly less) and it only contributes 15% meaning it is 15/48=31.25% effecient not very good at all!!! steam engines have been known to approach 50% and on rare occasions pass it!!! meaning thisa system should be giving about 24% to the overall effeciency!!!

[Matra et Alpine]

high, as noted earlier a 50% steam engine needs to go double or triple expansion, which adds complexity and size and WEIGHT. So BMW would seem to have identified the optimal compromise point with a lower efficiency steam energy recover option.

[Alastor]

what is the colour of the sky in your world???

Apparently the same color as Willard Pulkrabek.

I have attached scans of pages 371 and 372 from his book Engineering Fundamentals of the Internal Combustion Engine 2nd Ed. , which are the source of my numbers.

actually in reality it is assumed that the engine extracts 30% to make mechanical power(this is not at the wheels this is in the cylinder) then roughly 50-60% rushes out of the exaust and 10-20% is absorbed by the walls and cooling system. to take a closer look that 50-60% that goes out the exaust gets even lower the second it leaves the head losing about 10% to the surrounding atmosphere (for a double walled exaust this number goes down to about 1%) of the 10-20% that is absobed by the walls and cooling system between 30-50%(depending on thermostat setting) of this goes through the metal and out into the surrounding air without going through the cooling system the cooling system grabs 50-70% of the heat and uses the radiator to dump that into the air. so my equation stands the steam engine gets about 48% of the total thermal energy (actually slightly less) and it only contributes 15% meaning it is 15/48=31.25% effecient not very good at all!!! steam engines have been known to approach 50% and on rare occasions pass it!!! meaning thisa system should be giving about 24% to the overall effeciency!!!

It would be nice if you could post the source of your information so I can look into it myself. Otherwise I will stick with W. Pulkrabek.

[h00t_h00t]

I hope they replace the horn with a steam-engine style whistle to finish it off.

[Matra et Alpine]

I hope they replace the horn with a steam-engine style whistle to finish it off.

and a nice chuff-chuff-chuff sounds as you accelerate away from teh lights

[QuattroMan]

this i like to see!!!

[hightower99]

Apparently the same color as Willard Pulkrabek.

I have attached scans of pages 371 and 372 from his book Engineering Fundamentals of the Internal Combustion Engine 2nd Ed. , which are the source of my numbers.



It would be nice if you could post the source of your information so I can look into it myself. Otherwise I will stick with W. Pulkrabek.

well my information is based off of real life measurements... off of over 200 different engine types from your average chevy V8 to several 2 strokes ranging from 5-500cc and once I measured a friends engine (a 1988 lamborghini countach 5000 quattrovalvole needless to say i was happy to oblige!!! )

the information in that book (Which I am sure I have somewhere) is mostly theretical and that it states in the book that in the real world those numbers won't be the same.

Sorry about the crack about the colour of the sky I keep assuming that everyone has done the same amount of research as me. I was assuming that you had gotten those figures from measuring a bunch of engines...

[hightower99]

high, as noted earlier a 50% steam engine needs to go double or triple expansion, which adds complexity and size and WEIGHT. So BMW would seem to have identified the optimal compromise point with a lower efficiency steam energy recover option.

not really effeciency is also affected by how well made the motor is... I have seen a small working model steam engine that I measured to 48.7% of the total thermal energy that was used in the boiler was turned into mechanical work! it was only a single cylinder with a single piston however I will agree that it is much better when a motor is double or triple expansion! (However I think that the BMW does have a double expansion system as a high pressure and low pressure system are described in the same system.)



EDIT: umm I overlooked the fact that the BWM steam circuits get energy from the exaust AND the cooling system giving it even more energy and it has both a high and low temperature expander... this means that it is sounding less and less amazing! However it says that they are still developing so I hope that they find another 5% in there somewhere

Edit:also it seems that Henk4's quote that the steam couldn't give the motor a 15% increase in milage and Power seems to be wrong as BWM claims that they get both!!! yeah it is looking better already!

[Alastor]

well my information is based off of real life measurements... off of over 200 different engine types from your average chevy V8 to several 2 strokes ranging from 5-500cc and once I measured a friends engine (a 1988 lamborghini countach 5000 quattrovalvole needless to say i was happy to oblige!!! )

the information in that book (Which I am sure I have somewhere) is mostly theretical and that it states in the book that in the real world those numbers won't be the same.

Sorry about the crack about the colour of the sky I keep assuming that everyone has done the same amount of research as me. I was assuming that you had gotten those figures from measuring a bunch of engines...

Then I take it you work some where with some kind of thermal test apparatus? How exactly do you go about to determine all the losses?

I suspect the exhaust is easy, assume ambient in and then measure temperature and pressure at the exhaust valve will get you in the ball park. Or perhaps a better measure is to use the static pressure and volumetric flow rate? Also, how is the un-burnt fuel accounted for?

For the coolant and oil, again measure the initial and final temperatures and pressures. Is the heat stored in the block significant at all? Also, to measure the heat lost to ambient does the test apparatus need to be in a thermal chamber?