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Why not a gas/steam hybrid engine?

  1. May 21, 2008 #1
    I know that the best engines today are only what about 20-30% efficient at converting the energy in gasoline to actual motion? Most of the energy is simply wasted as heat. So why not make an engine that is a hybrid between gas and steam? Why not use all of that thermal energy that is wasted from the combustion of gas to heat water into its vapor phase to power half of the steam engine? Could this be done practically?
  2. jcsd
  3. May 21, 2008 #2
    search "crower engine"

    pretty cool
  4. May 22, 2008 #3
    Why not a gas/steam hybrid power?

    Yes, why not? Our company is developing steam and gasoline hybrid power technology. Our test results have shown that you can increase the fuel efficiency to 40% or better with corresponding or better reduction in the emission levels.

    Abdul A. Mitha
    Clean Power Technologies Inc.
  5. May 22, 2008 #4


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  6. May 22, 2008 #5


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    It's worth noting that you'll never be able to recover and use all the waste heat.
  7. May 24, 2008 #6

    I was about to mention that as well.

    I guess the only drawbacks to such a system is added cost and weight...and that heat collection system isn't perfectly efficient either.

    Ideally, we'd be stepping away from gasoline/diesel engines and utilizing plug in cars, for one example. The electricity generated from our current power plants are relatively more efficient than individual internal combustion motors, so...
  8. May 25, 2008 #7
    But, if you use a steam engine there will be a greater removal of heat from the engine, possibly eliminating the radiator and the radiator fan.
  9. May 25, 2008 #8

    Well based on the said model, the heat is scavenged from the exhaust heat, so there is still heat that is coming from the combustion itself that is distributed around the engine block, so a radiator will be needed.

    But then that does raise another area that heat can be collected, so...we'll see. This is all fine and dandy, but I find the idea of replacing internal combustion engines entirely with a new means for an energy source to be easier and more efficient overall.
  10. May 25, 2008 #9
    Isn't a turbo used to capture exhaust heat?

    How about using ceramics instead of steel/iron in the cylinder block and pistons, there wouldn't be as much waste heat from the engine block. The high temperatures could also lower emissions and heavier fuels could be burnt.
  11. May 25, 2008 #10

    Well, sort of. The turbine on the compressor side of the turbo is spun by the hot exhaust gases flowing through it...kind of a transfer of momentum from the exhaust gas particles rather than a heat transfer process.
  12. May 26, 2008 #11


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    Yes, a turbo does capture exhaust heat. However, the heat rejected to jacket water through the head and block is a necessity for the engine to operate (ie you need to cool the engine!). Some manufacturers are actually looking at coating in-cylinder components with thin ceramic layers, but these by no means replace steel, iron and aluminium. If you insulated the combustion chamber, the excess heat would be carried out in the exhaust instead. Obviously there's the potential to capture this with the turbo (and running an engine with as high a jacket water temperature as possible improves efficiency), but other rotating/sliding components begin to suffer at much higher temperatures (due to loss of clearances, and reduction in oil effectiveness). High combustion temperatures don't necessarily "lower emissions"; NOx actually increases with higher peak cylinder temperatures; and heavier fuels need a lot more than just higher in-cylinder temperatures for successful use.
  13. Jun 1, 2008 #12
    Dear Sir,

    I have been writing in my journals for 30 years about a conversion I wanted to make to the gas guzzling V-8 engines. My idea has been to use two outside cylinders on one side as gas cylinders without modification. The other side inside cylinders would also be used as gas cylinders without modification. These four cylinders would be modern fuel injected with all normal computer controls. The engine must be run on these four cylinders until proper block and head temperatures are achieved. Then the four remaining cylinders would be run as two stroke units being powered by “flashsteam” injection at top dead center of the steam cylinders. The exhaust from each gas cylinder would go out of its normal exhaust port and loop around to its adjacent steam cylinder old exhaust port. The old exhaust valve and seat in the steam cylinder will be replaced with a “heat sink” which extends into the old combustion chamber and thereby replacing it. The other side of the “heat sink” will have fins on it extending up through a hole milled in the head which replaced the old exhaust valve. A stainless steel tube will be press fitted in that hole which holds that “heat sink” essentially blocking any flow into the steam cylinder. But the exhaust gas from the adjacent gas cylinder will flow through a side hole in that SS tube with the fins of the “heat sink” protruding upward. This new exhaust tube will have to come out of a hole cut in the old valve cover. There will be two such holes in the old valve covers directly in line with the replaced old exhaust valves. The original intake valves of the converted cylinders will become the new exhaust valves for the new steam cylinders. They must be controlled by a special cam shaft which has a double lobe for each of the new steam exhaust valves. This control will be to open the steam exhaust valve at bottom dead center and close it on top dead center using two new lobes on that cam position. There will be four such new double lobe cam positions. The original exhaust lobes for those cylinders will not be used. A new simplified intake manifold must be fabricated to provide normal injector placement and connection to the throttle body for the gas cylinders. A new manifold from the original intake holes on the steam cylinders which are now steam exhaust holes will be joined to the new SS gas exhaust tubes coming out of the valve covers which will mix the spent steam with the gas exhaust to be outputted to the atmosphere through normal modern exhaust systems. A computer control of the “flashsteam” injectors must be provided. The idea of using a “Corn Burner” as a heat source has been modified by using the waste heat from the standard internal combustion engine. I am not mixing water or steam into the gas cylinders. The gas cylinders will be unchanged physically or in their normal operation; just their exhaust will be diverted a bit. Limiting some of the water cooling around the new steam cylinder and head should be done to retain their heat. The “flashsteam” injector may be the proper way to run the steam cylinder. I have wanted to make what I call my “Hybrid Steam Engine” for years. Every time the price of fuel goes up, I get more interested in its development. Now the fuel price has pushed me to accomplish my goal. But I do not feel the idea or which could be an invention needs to be held in private for financial gain. I have told many people about the idea without any action. Now with the Internet, maybe this idea will catch the eye of people of the World and not be squashed by the oil companies. Keep in touch because I have some other good ideas such as fine gold recovery and owner builder home construction.


    George J. Birds Jr.
    Last edited by a moderator: Jul 9, 2008
  14. Jun 1, 2008 #13


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    Well, it might help a little, but steam engines still have heat rejection, via a condenser.
  15. Jun 1, 2008 #14
    There was an article in Popular Science (or is it mechanics?) I read on a plane about a race car mechanic that had made a 6-stroke engine that did just that. It was in the May or June issue of 2007.
  16. Jun 2, 2008 #15
    Good morning forum and gas guzzlers 06-02-2008 11:26 AM

    Attention: V-8 Engines, it is time to change your eating habits. You are going to have your gut detoured to scavenge some of your waste heat. You are not going to have to use four of your gas cylinders on your eight cylinders engines to run any more. You can have four cylinders with gas; but the other four cylinders will provide power without you expelling hot air. The four converted cylinders will not be letting out your energy just to raise the air temperature around you.

    Attention: Drivers of V-8 Engines, do your part to encourage the development of a more efficient internal combustion engine. Be at least interested in ideas to ultimately save your cash and our energy supplies. Enthusiasm is the spice of life; and it will provide rewards. That is better than complaining over a cup of coffee. Positive feedback with constructive criticism is what we inventors need to put our ideas into a working prototype. At least, you can see from my contributions that I am attempting to help our energy situation with positive suggestions.

    Attention: Inventors, car buffs, steam engine masters, and others with positive feedback, make your contribution to an energy efficient internal combustion engine. Remember, it doesn’t have to be something that needs new castings. Electronic control is common place now. Rust resistant injectors are available. Bring up your problems with the idea in a positive way with alternative approaches. Let us all work toward a common goal which is to finally keep more of our hard earned cash in our pocket instead of paying through to nose for our fuel to propel our vehicles.

    Attention: Big SUV and pickup drivers, wouldn’t it be wonderful to take your gas guzzler vehicles into a modification shop to have it converted to a hybrid steam engine. There is enough carrying capacity for this energy modification of your gas guzzler vehicle which is upside down in value of typically $10,000 because no dealer will give you jack poo for it toward a new small energy efficient vehicle. Talk about this hybrid steam engine idea that I have proposed. There must be engine builders to help make a prototype.

    Attention: As the writer of this hybrid steam engine, I will continue to make a prototype. In my following contribution letters, I will be more specific on the necessary modifications and my progress in making a prototype. I even am thinking about making my own camshaft by wilding and regrinding four of the lobes by following the contour of other lobes which will give me necessary lobe with two high sections. I am not worrying about things like angles just as long as the valve opens at bottom dead center and closes at top dead center. Remember, this hybrid steam engine is not a 6-cycle engine. It is still a 4 cycle gas engine on the four remaining gas cylinders. The four steam cylinders are now 2 cycles with a power stroke on every downward movement of the piston. No gas is mixed with water. No worry about heat losses because that is exactly what the hybrid steam engine does to the block heat as well as the exhaust heat. As far as heat rejection, and condensers in steam engines, that will be something to consider for better efficiency and water consumption. But if all I need to do is to add distilled water to my tank and drive the hybrid steam engine to work with its normal fuel supply, I can do that. I can even collect rain water to use a water supply. As far as freezing in cold climates, that will have to be addressed in a positive way. Water getting into the crankcase from the steam cylinders must be addressed; but has anybody tried water soluble oil in their crankcase? The automatic machining industry use soluble oil in all of their high speed cutting machines to cool and lubricate their cutters. My contribution to this forum will be positive with as much help to others to keep their enthusiasm.


    George J. Birds Jr.
    Last edited by a moderator: Jul 9, 2008
  17. Jul 9, 2008 #16
    Thirty five years ago when I was an Apprentice Machinest in an engine plant I attended a lecture on heat transfer and its effects on engine components,the lecturer remarked back then the internal combustion engine has had it's day as fuel costs rise it will become more apparant of it's inneficiances and short commings as is evident today.

    Part of the lecture was comparing an internal combustion engine to a Steam Boiler where it was pointed out the average 6 cylinder combustion engine needed aproxamitly 20 liters of water for the sole purpose of dispercing waste heat, if you were to build a steam boiler of the same water capacity you would be hard pressed to bring the water to boiling point on the same amount of fuel as quickly as an internal combustion engine could, modern engines today have made only slight differences to this basic comparison in fuel economy they produce the heat even faster, friction has been improved but negated by the engine producing higher hp at higher rpm,at best 5% efficancy improvement over all in thirty five years.

    Ceramics are not the answer they suffer from thermal shock the rise to operating temprature is to quick and further exasperated by varing forces of load = more heat.

    Building engine blocks out of light weight alloys for heat transfer is part of the answer, a hybred that disconnects them from the drive after building up steam then using them as a boiler powering a crude piston steam engine would be a more efficient use of now precious fuel resorces.

    If any one thinks this is a rediclious path then remove your fan belt and cover your radiator
    sealing off the cap put a pressure gauge in and get a stop watch start your engine and watch what happens, try boiling the same amount of water to the same pressure with the exact amount of fuel used, you will then realize the internal combustion engine is one of if not the best and cheapest ways of producing steam ever devised. its pressure is only limited to a re design of the block to withstand higher pressures, far less than the combustion chambers are subjected to during combustion both in pressure and tempratures and far less than a modern steam boiler could operate at.

    It's only because fuel is still convienant cheap and plentiful that the recriprocating inturnal combustion engine is still in use today, imagine your v8 giving 18% effiency as the main tractive power then getting 80%+++ as a hybred steam boiler for far less fuel driving even older technology in a recriprocating steam engine.

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