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Formula For Calculating Output Power of a Turbine

  1. Sep 26, 2016 #1
    Good evening,

    This Conversation is in regards to questions i have of a project of mine. I am, in a sense, looking to make a generator of sorts, one that uses a magnetic tesla turbine in order to power an electric motor. Unfortunately, i am at a loss for what formula i would need to figure out how much power (volts) this turbine will generate. I realize that the weight, diameter and speed of this turbine is all apart of calculating the total power it will produce. Question im looking for is simply, what formula do i use?

    I know there are many factors that will effect the total voltage generated, for instance number of copper coils or if you use a booster cercuit or not. Let us say that the fluid used to turn the turbine is simply pressurized water, will the total force from the PSI be included in a formula to find the amount of power, or would you just use the overall speed of the turbine? Feel free to add any comments you may have.
  2. jcsd
  3. Sep 26, 2016 #2


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    To answer your questions directly would require distilling several years of technical education and experience down into just a few postings .

    In any case there is not going to be just one formula .

    There are some simple calculations for working out basic quantities like the theoretical maximum power which can be generated from an available water flow .

    Realistically though many other calculations would be needed to properly optimise your design - you would probably be better off using some inspired guesswork and a lot of trial and error .

    We 'll have a look at your design if you post a more detailed description and some drawings .
  4. Sep 26, 2016 #3

    In regards to your statement on there realistically being many other calculations needed to find the total power output, i realize that the answer to my question must rely on not just various calculations, but knowledge from experience as well. Both of which i am more than willing to tackle. You sound knowledgable on what must be done to find such an answer. Unfortunately, my projects schematics arent available. However, if there is any further info i may provide let me know. If you would rather answer my question through email than using posts let me know, either way i am more than interested in learning how to solve something like this.
    Thank you for your time in looking over my post
  5. Sep 26, 2016 #4


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  6. Sep 27, 2016 #5
    Generally U.S. makers rate their turbines by the measure of force they can securely create at a specific wind speed, for the most part picked between 24 mph or 10.5 m/s and 36 mph or 16 m/s. The accompanying recipe represents elements that are imperative to the execution of a wind turbine. Notice that the wind speed, V, has a type of 3 connected to it. This implies even a little increment in wind speed brings about a vast increment in force. Perused How high ought to your little wind turbine be for more data. That is the reason a taller tower will build the profitability of any wind turbine by giving it access to higher wind speeds as appeared in the Wind Speeds Increase with Height chart. The recipe for figuring the force from a wind turbine is:



    P = Power yield, kilowatts

    Cp = Maximum force coefficient, running from 0.25 to 0.45, measurement less (hypothetical most extreme = 0.59)

    ρ = Air thickness, lb/ft3

    A = Rotor cleared zone, ft2 or π D2/4 (D is the rotor width in ft, π = 3.1416)

    V = Wind speed, mph

    k = 0.000133 A consistent to yield power in kilowatts. (Duplicating the above kilowatt answer by 1.340 proselytes it to torque [i.e., 1 kW = 1.340 horsepower]).

    The rotor cleared zone, An, is essential in light of the fact that the rotor is the part of the turbine that catches the wind vitality. In this way, the bigger the rotor, the more vitality it can catch.

    The air thickness, ρ, changes somewhat with air temperature and with rise. The appraisals for wind turbines depend on standard states of 59° F (15° C) adrift level. A thickness redress ought to be made for higher heights as appeared in the Air Density Change with Elevation diagram. A rectification for temperature is ordinarily not required for foreseeing the long haul execution of a wind turbine.
  7. Sep 27, 2016 #6

    This may in fact be the formula i am looking for, i will need to do more research on it though. In the Meantime i do have a question about this equation, assuming you know what it's talking about...It speaks of high and or low gross head. Now i know what head is, but is this really a factor if i am using essentially a pressure hose? Thank you for providing this information to me.
  8. Sep 27, 2016 #7


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    Sorry if you know this already but..Head and pressure are related. You can convert the pressure in your hose to an equivalent head.
  9. Sep 27, 2016 #8

    You're absolutely right! Thank you for reminding me, its been awhile since i have touched base with this sort of topic.
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