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  1. N

    DIY Tesla Impulse Turbine

    Little by little.... ;)
  2. N

    Compression ignition

    Of course, I know a solenoid actuated injector, not being mechanical, is less fun; but have you thought at one? Thus, the size of pump could be reasonably higher. And think a simple microcontroller could be able to drive it. Later edit: Yes, an electronic control of a unit like that presented...
  3. N

    DIY Tesla Impulse Turbine

    Thank you, Steamchick, for sharing your experiments and the theoretical info, and I would love to hear more about results of your trials. Some pictures would be more than welcome!
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    DIY Tesla Impulse Turbine

    Fun fact: dental turbines use gaseous bearings. If you have low side loads, they are optimal for extra-high rpm-s. Don't know if they work well with TT, either alone or in certain combination. For a home-built model, though, ceramic bearings should be preferred. They offer high precision and...
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    DIY Tesla Impulse Turbine

    Another thing that concerns me at Tesla turbine: I know from wind power plants and similar applications that there is a certain proportion between gas speed (wind) and rotor speed at which energy transfer (efficiency) is maximum. There is a certain formula I can't recall. I don't know how this...
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    DIY Tesla Impulse Turbine

    Haven't thought of it!
  7. N

    DIY Tesla Impulse Turbine

    One thing that doesn't fit my mind is why Tesla turbine doesn't like backpressure! As I figure it (and was described by its inventor), the mechanism is based on micro-adhesion between steam molecules and turbine disks so a direct transfer of kinetic energy from steam to rotor; no other...
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    DIY Tesla Impulse Turbine

    Hi Steamchick. I have little experience with Tesla turbines - I mean even from informal point of view. From what I have read, it seems many had poor experience with it (I mean low efficiency even in ideal conditions - dry steam or alike) while few have hit the bull's eye. I think the efficiency...
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    Compression ignition

    In fact, you are right, Minh-thanh; most high octane gasoline has antiknock additives. only those allow high compression ratios without issues. Though, in many engine operating conditions - for a c.r. 12-1 engine-, compression does not start from 1 bar; engine being partly choked on its...
  10. N

    Compression ignition

    Hi, I don't know if I should enter such hot discussion. I have read some engine books, most appearing in 1950-1990. First comment, as an interesting example for the case. Free piston engines were (and still are) one of St. Graal of IC engines. At the level of 70', Sigma(France) and...
  11. N

    Monotube Flash Boiler Design

    Maybe I'm wrong but I believe even swapping to final fluid with its own viscosity curve might require another final tuning - lots and lots of diagrams to get closer to the truth... Luckily, electronic control comes in support. Care should be taken, though, for stable vs unstable processes -...
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    Monotube Flash Boiler Design

    I really take care not to push any button too much... Love to see development of experiment and consequent corrections. And respect for using digital support -something still far for me; at least in what concerns software understanding and put-to work!
  13. N

    4 Cylinder Inline Engine

    What I have said above comes to add to K2's details. Uneven mixture is both effect of suspended fine fuel particles in air flow that has a rhythmic beat on cylinders and a continuous flow of a film coming from larger fuel particles which adhere to manifold walls. Both have higher inertia and...
  14. N

    4 Cylinder Inline Engine

    If engine is not intended for performance but for smooth running, this might be of help (sometimes hot spot is bath shaped and diverts air flow 90 deg. to retain and vaporise gas droplets). But this is old technology, mating with less-than-perfect carbs...
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    4 Cylinder Inline Engine

    Maybe last templar, half knight half monk; and living in a cave :) . As I think the problem is much more complex (we were discussing here just one of the most simplified models, but if you want to go deeper, you notice it is half meaningless, unless you take in consideration other factors...
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    4 Cylinder Inline Engine

    I guess, but not by me :) ! Last serious calculations (excluding +,-,x,: ) I have done maybe 30 years ago... Please let me return to my cave! And I am not ironic. Any knight needs an ideal to continue to fight ; be it Holy Grail, crusade, wealth or love...or other. I have already defined...
  17. N

    4 Cylinder Inline Engine

    F is resultant of forces acting on analyzed half of crankshaft. F1 is resultant of forces acting on the other half of crankshaft. Situation is mirrored on either halves. This was my judgement. Cheers!
  18. N

    4 Cylinder Inline Engine

    Yes K2, that-s what I thought; on static, forces on both halves being on the same magnitude (not equal) looks like central bearing acts partly like a fixed attachment point for each one half. And I said (and meant) just a bit more stiffness. Of course, my "simulation" was also entirely mental...
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    4 Cylinder Inline Engine

    I think is even a bit more than your estimation. First, 2 bearings, due to internal play, do not take any bending load (torque); central bearing is much evenly loaded on both sides and takes much more pure radial compression. And, as bonus, the other side of crankshaft (if we judge one half)...
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    Monotube Flash Boiler Design

    As the cherry on the cake, in 80's I have read a book about Ranque-Hilsch Vortex Tube - RHVT and its current (or intended) applications. https://www.airtx.net/airtx-vortex-tubes-review Today you can struggle to find something about it.... But at those days, mathematical description/modeling of...
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