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Boiler volume for specific steam turbine?

  1. Sep 13, 2016 #1
    New here, hope someone can help.

    I'm experimenting with a heat source for a steam turbine. I have the specs for the turbine and the necessary conditions for operation, but at this point in my design I need to figure out the volume of the actual boiler/reservoir. A direct answer or the right equation would be infinitely helpful. Thanks in advance!

    Superheated steam 10- 12 bars abs. 200-220 degrees C
    Steam consumption: .04kg/second
    basic steam rate: 9.8kg/kwh
    Other useful I formation: For the 15 kW you will need a steam boiler of minimum 150 kW / 160 kW / 180 kg/h.
  2. jcsd
  3. Sep 13, 2016 #2


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    Staff: Mentor

    Welcome to PF!

    Volume isn't really a relevant parameter for a boiler; what matters is surface area of heat exchange. It sounds like you are saying you are designing this boiler from the ground-up and heating using a heat source of your own design. The nature and capacity of your heat source will determine what the boiler should look like.
  4. Sep 13, 2016 #3
    My heat source can be tailored to the exact temperature needed to run the turbine. What I need in order to design and manufacture it is the size of boiler needed at the optimum temperature etc. I can adjust the heat source to whatever is necessary, but in order to build the boiler I need to know the minimal size needed to run the turbine. (Based on the requirements listed previously.)
  5. Sep 13, 2016 #4


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    Staff: Mentor

    That's great: and you gave the steam flow rate and pressure/temperature, so we know the required capacity of the boiler. But again:
    Again, physical size is not directly related to capacity. For example, a gas fired boiler is much, much larger than an electric boiler of the same capacity (example, in the capacity range you need, about the size of a refrigerator: http://www.cleaverbrooks.com/Products-and-Solutions/Boilers/Electric/Model-CR/Index.aspx ). You will need to design the boiler based on how you intend to heat it. So: how exactly do you intend to heat it?

    Edit: Also, please note that boilers and steam power systems are very dangerous. Due to the level of knowledge that is implied by your question, we may have to close this thread for safety/liability reasons (right now it is a bit vague to know for sure what you are attempting...). If you really don't know what you are doing and you are attempting to design/build your own steam power plant, I urge you to reconsider. People die this way.
  6. Sep 13, 2016 #5
    Forgive my wording. I meant volume. I'm not as concerned about the actual physical size. That will end up being a factor of the design itself. Once I know the volume necessary for fluid heated to the proper temperature to run the turbine, I can move forward.

    My design is electric in nature. The reason I need to know volume, is so I can determine if the electricity needed to run my heating elements is more or less than what the 15kw generator can produce. My heating elements produce much more wattage of heat than electricity they use. I'm fuzzy on the math, but this has been the focus of a lot of my research.

    I'm also curious about using ORC fluids in place of water for the steam. From what I've found, ORC turbines can run on much lower temperatures than steam turbines.

    In fact, adding something like acetone to water reduces its boiling temperature significantly. From what I have read it also bonds with the water atoms unlike alcohols and the like. Using such a mixture as a working fluid for the turbine would require less heat, and less wattage, without the difficulties associated with distillation of the mixture.

    If I'm totally crawling down the wrong path I'm absolutely open to critiquing from those who know better. That's why I'm here.
  7. Sep 13, 2016 #6


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    Science Advisor

    That defies the law of conservation of energy.
    Perpetual motion machines are science fiction and are a banned topic here at PF.
  8. Sep 13, 2016 #7
    I forgot to add "under the right circumstances." This is why I was hesitant to explain my heat source. My original question still stands, despite the science fiction.
  9. Sep 13, 2016 #8


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    Staff: Mentor

    I know you meant volume - I said volume. You really aren't listening and we are going around in circles. Furthermore:

    This is impossible and since you are "fuzzy on the math", probably just an error on your part. This thread is closed for three reasons:

    1. It is non-productive because you aren't listening to what you are being told.
    2. We don't discuss perpetual motion here.
    3. This is dangerous for someone with your level of knowledge to attempt and for liability and safety reasons we can't be a part of it.

    I'm fuzzy on the math, but this has been the focus of a lot of my research.
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