Recent content by rpp

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    Reproducing (almost) Oklo reactor conditions in the lab

    This is a very ambitious science fair project, and it sounds like your stepdaughter is pretty creative. I'll just answer one part of your question - why this wouldn't work. First, the main reason that the Oklo reactor worked is that the uranium enrichment when Oklo was active than it is today...
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    Atomic density of Oxygen in a composite

    This is a fairly complicated calculation and you need more information to do it correctly, specifically you need to know the densities (usually in g/cc). You also need to know the "plutonium vector" of the plutonium oxide. Does the uranium oxide contain any U234 or U236? If you know the...
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    Neutron flux and current

    In nuclear engineering terminology, the "scalar flux" is usually the angular flux integrated over all angles. Technically the angular flux is also a scalar value, but it is the flux with direction "omega". I think this agrees with what you are saying, but the term "scalar" may cause some...
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    Westinghouse Very Small Modular Reactor Progress

    The reactor is composed of fuel and heat pipes. The fuel generates heat, the heat pipes then transport the heat to a heat exchanger, which then heats up the gas. There are no moving parts in the reactor itself. There is moving fluid in the heat pipes, but this isn't considered "moving...
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    Codes to calculate diffusion parameters of homogeneous reactor

    What is the purpose of these calculations? One-group diffusion theory is going to have "limited accuracy". If you are just doing a back of the envelope calculation, this is fine and you can find values of one-group cross sections and L^2 and D in most introductory reactor physics books. (The...
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    Help debugging MCNP code - particle lost and zero latice element found

    To give a few more hints, search for "interactive plotter" in the manual and use the "ip" option on the command line.
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    MCNP FMESH for Plotting power distribution

    I don't think FMESH is going to work for you because FMESH uses an x-y-z grid and your reactor geometry is hexagonal. Even if your reactor was on a square grid, it still uses circular fuel rods, so FMESH isn't going to work. What are you transferring to the CFD calculation? As @Grelbr42...
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    MCNP lattice of the fuel assembly input file?

    I'm not sure what your final objectives are, but this assembly is at room temperature. I've attached an input for a 16x16 case that uses a fuel temperature of 900 K and all other temperatures are set at 600 K. Unfortunately, this doesn't use lattices and the pin diameters are slightly different...
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    I get this error when I try to run the code MCNPX

    I just looked at your previous posts, and it looks like several people have tried to help you set up your MCNP cases, but you don't appear to understand the very basics of how to set up the code. Instead of randomly "trying things", I suggest sitting down with an example input and going through...
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    I get this error when I try to run the code MCNPX

    There are many problems with this input. Have you tried to look in the manual and example problems? I would start with one of the example problems distributed with the code and try to understand how it works. The "fatal error" message tells you exactly what the problem is. The keyword...
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    I get this error when I try to run the code MCNPX

    I'm not sure if this is the problem or not, but the first thing I noticed is that you need single blank lines after the cell card definitions and after the surface card definitions to define the different "input blocks". Insert a blank line after line 10, and after line 21 (which will be 22 if...
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    Simulate3: Modeling 3-Batch Equilibrium Cycle for PWR

    Look at the example files included with the code. There is a PWR example problem that exactly does this.
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    Does radon remain inside solid radium?

    The quick answer is that some will escape and some will remain in the solid. The longer answer is a lot more complicated. As others have pointed out, when radon is produced by the decay, it will impart energy on the lattice and will damage it. The radon gas (and helium) can migrate/diffuse...
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    Nuclear Energy reading material

    I certainly agree with this. The first and the best. However, I'll stand by my statement that it is pretty rare for somebody with a nuclear physics background (not nuclear engineering) to work in the nuclear engineering field. It does happen, but it isn't common. The engineering degree...
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    Nuclear Energy reading material

    Note that "nuclear physics" and "nuclear engineering" are different things. Nuclear physics is more interested in the science aspects, including quantum mechanics and what makes up an atom. Nuclear Engineering is the application of nuclear energy. While you need to know the basics of nuclear...
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