Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

Register Log in
  • Congratulations TugboatEng on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

Search results for query: *

  • Users: TSLexi
  • Order by date
  1. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    That's a better idea. We can divert the steam into a turbine, and use the oxygen to power a gas turbine, and connect the two shafts.
  2. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Yeah, azmio3. And if we use hydrogen peroxide to augment the oxygen from the forced induction system, we can get more complete combustion, which means higher power and lower BSFC.
  3. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Actually, BigClive, Mr Crower fell ill, so he couldn't finish development. And no-one's figured out yet how to deal with the corrosion from the hot steam, and make sure the steam doesn't wash away the oil.
  4. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    I have checked the prices of industrial-strength 70% hydrogen peroxide. It's $0.45/lb. Diesel is a bit more expensive per pound, around $0.57/lb. If the hydrogen peroxide is 70% or above, it's hypergolic with organic materials. You just need to keep it away from light, in aluminum containers...
  5. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    My main point, Greg, is trying to extract has much work from fuel as possible, and the best way to do that is to make sure the fuel combusts completely, and all the energy from the heat is used as well.
  6. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Basically, the same idea as before, but using hydrogen peroxide, a powerful oxidizer, instead of water, which I'm no realizing wouldn't quite do as much, as all it does is boil, still leaving contaminants. We could also inject the hydrogen peroxide during the intake stroke, right before the...
  7. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Maybe we could inject hydrogen peroxide after the power stroke when the piston is at TDC to oxidize any UHCs, PMs, and CO remaining after the diesel combusts. You then have to deal with the nitric and sulfuric acid formed from the oxidation of the NOx and SOx, but you could probably neutralize...
  8. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Since the exhaust will be too cool to activate the turbo, couldn't we just use a supercharger for forced induction instead? Sure, we lose some percentage of power, but it should be made up.
  9. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Wow, Achates Power and me have the same idea kinda (theirs seems more thought out though)! I mean, about the cylinder design.
  10. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    OK, but my theory based around recovering some energy from that hot exhaust. As long as the EGT is 500-800 degF, the catalytic converter will operate. Any temperature above that is wasted energy. Also, perhaps a way to extract more work would be to have opposing pistons linked together by...
  11. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    tbuelna, my reasoning is that the exhaust gases from combustion are quite hot (EGTs are routinely 1200+ degC), and by having the piston recompress those gases, and then injecting water, the water will be vaporized, which will provide force to push the piston back down, and also reduce EGT. High...
  12. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Yeah, perhaps trying to use the turbo as an alternator would be wasteful. Although using an ultracapacitor may have merit. A variable-geometry turbo would be better. So in order to reduce NOx emissions, we need to reduce hot spots in the cylinder, by making sure the air and fuel are thoroughly...
  13. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    I also wonder if placing a squirrel cage generator between the turbines of the chargers, will help recover some of the energy lost, as we could use it to charge the car battery, and when the engine's exhaust speed is too low to drive the turbine fast enough to provide the desired boost, we could...
  14. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    I think you could sell the idea of having to add water by the savings on fuel.
  15. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Keep it from freezing by adding methanol to it. And the sound...that's a feature. some people like loud engines. You could dampen it with active noise cancellation technology as an option.
  16. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    So, from reading that, water injection increases power while decreasing BFSC, and water contamination of the oil can be avoided by aiming the water at the piston head rather than at the bore walls. And it decreases NOx. And I believe the problem of SOx and UHC and CO emissions can be solved by...
  17. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    I think carbon fiber-reinforced silicon carbide would be a great material to build this engine, as it has a high melting point, high thermal shock resistance, and a high strength/weight ratio. I mean, if it can be used in high-performance brake pads, why can't you use it for the engine's moving...
  18. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    I guess I could get some money together to build a small W4 motorcycle engine from this concept.
  19. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Well, my idea of having a steam stroke is to decrease the amount of diesel needed. Twincharging can be utilized to decrease the amount of diesel needed, as higher oxygen density means more complete combustion, which means more work can be extracted from a given amount of diesel, and less...
  20. TSLexi

    Compound expansion plus water injection to increase fuel efficiency of a Diesel cycle engine?

    Thanks Brian! Also, I now realize injecting water along with the fuel would be a bad idea. But I was originally talking about injecting water after the exhaust stroke when the cylinder is at TDC, letting it expand, get exhausted, and THEN have the next air intake stroke. And Atkinson cycles...

Part and Inventory Search

Back
Top