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  1. FredRosse

    Diesel Common Rail Injector Pump Drive System

    We have Diesel/Dual Fuel Engine-Generators, with a new "Micro Pilot" fuel oil injection system, a modern common rail high pressure system, with electronically controlled injections. The engines are rated at 2500 kW, 400 RPM, 17 x 22 B&S, inline 8 cylinder engines, direct coupled to their...
  2. FredRosse

    PM DC MOTOR AS GENERATOR

    The motor is rated at 24 VDC 30 Amps, and I have two deep cycle 12 Volt batteries in the setup. A simple relay system (two DPDT relays) switches to have the two batteries in parallel for 12 Volt operation (low speed), or arranging the two batteries in series for 24 Volts (hi speed). With the...
  3. FredRosse

    PM DC MOTOR AS GENERATOR

    I have made a home generating system (Diesel Cogeneration) where a small Diesel engine directly drives a simple single phase AC induction motor. When the Diesel engine drives the motor above synchronous speed, it becomes a generator, delivering power to the grid or my house, and when the...
  4. FredRosse

    Moment of Inertia?

    in the vicinity of 5000-7000 kg-M^2, but the OEM should have this information.
  5. FredRosse

    VFD Minimum Output Frequency

    Can typical (60 Hz input, 100 + horsepower ) VFD drives allow output at say, 1 Hz, 10 Hz, 30 Hz ? I understand that driven equipment may have problems at very low speeds, but the question here is if VFD systems usually have a "built in" minimum output frequency, or can you set the VFD at ...
  6. FredRosse

    Water coooling chamber, will turbulence on opposite side help?

    "If the current design is laminer flow and the 'bumps' increase mixing, then they will help. If the flow is already turbulent then I don't see them helping at all." Don't agree with this, more turbulence always increases heat transfer coefficients (HTC). Transition from laminar to turbulent...
  7. FredRosse

    how much steam lbs/hr will a dryer take

    "My process requires 500 CFM of at 200 Deg F" That is 1808 pounds per hour of air. Temp rise is 75F to 200F = 125F x 0.24 BTU/LBm-F = 54250 BTU/hr heat flow "steam coil injected with 60 PSIG sat steam" That steam pressure corresponds to a saturation temperature of 307F, and the latent heat of...
  8. FredRosse

    Energy content of a fuel - mixture with H2O

    "I understand that generally heating values are for 100% moisture-free material unless otherwise stated." That is almost never the case for my industry, which burns all kinds of solid, liquid and gaseous fuels. In combustion and heat value calculations the distinction between High Heat Value...
  9. FredRosse

    Control valve position

    Fluid flashing downstream of the control valve (this is cavitation) should generally be avoided, and there are so many fluid system variables that would give upstream/downstream preference that much additional specifics would be needed to answer the control valve cavitation question alone. Also...
  10. FredRosse

    Controlling the temperature drop in a duct

    The duct is treated as a simple heat exchanger, I am assuming it is cooled by natural convection of ambient air on the outside, and heated by forced circulation electrically heated air on the inside? Increasing the mass flow of the heated air will decrease the temperature drop in the duct...
  11. FredRosse

    Letdown valve

    willard3 "The second law of thermo predicts there will be a loss at a pressure reducing station." What do you mean here? And what is the relevance to the posted questions?
  12. FredRosse

    Removal of ethanol from gasoline

    140Airpower - "Fred, All of these engines are alcohol intolerant?" I do not know, but several have started to have problems which point to the typical ethanol issues so often cited. This comment has nothing to do with the original posted questions. "It looks like you are going to be doing a...
  13. FredRosse

    Removal of ethanol from gasoline

    ---tbuelna "It would be far easier and less costly to simply replace a few fuel system components with ones that are compatible with gasoline containing 10% ethanol." I don'tknow what planet you are from, but that statement certianly does not apply here on earth. Maybe $100 for each...
  14. FredRosse

    Removal of ethanol from gasoline

    tbuelna: (Aerospace)18 Aug 15 05:15 "All gasoline sold in the US now contains at least 10% ethanol" That is not true. Gasoline with no ethanol is sold in every state of the USA. Often not convenient to buy it, but it can be bought.
  15. FredRosse

    Trailer roll over

    "don’t forget that that lower tire will be over loaded and deflected more than the high side tire, for some added tipping effect." True, also more deflection here if the trailer has springs on the axles. Centrifugal force can (and should) be also accounted, Fc = M V^2/R, where Fc is the...
  16. FredRosse

    pumps of different head in parallel operation

    Two (or three, or four etc.) flow circuits in parallel will each have the same differential pressure, or head differential. This problem lends itself to easy graphical solution. Each pump circuit has its own pump curve, and a unique head loss for the local piping, valves, orifices within...
  17. FredRosse

    Removal of ethanol from gasoline

    Interesting that several inputs to this thread talk about all kinds of things, but most of them do not address the original stated questions. I tried to eliminate unwanted comments in the original post, indicating that I already knew that octane rating would go down with ethanol removal, I...
  18. FredRosse

    Removal of ethanol from gasoline

    "I should also mention that E10 meets fuel specfications with the ethanol included." What do you mean by this? What fuel specifications? The original questions are asking about fuels for engines built 50 years ago.
  19. FredRosse

    Letdown valve

    Yes, the throttling process for steam generally resilts in lower temperature, at least in the pressure/temperature regimes we humans typically use. At very high temperatures steam begine to behave similar to an ideal gas, and throttling process here is very nearly isothermal. When throttling...

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