Recent content by Lucky mkhonza

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    Calculating Probability of Failure for a Series Cooling Circuit | Dear Folks

    "What is the probability that the cooling circuit corresponding to the scenario arranged above fails?" Let us assume component (1) Heat exchanger (probability = 10^(-4)/requirement), (2) Pump (probability = 10^(-3)/requirement) and energy to the pump (probability = 10^(-3)/requirement) are...
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    Calculating Probability of Failure for a Series Cooling Circuit | Dear Folks

    Dear folks, Please help me in assessing the following scenario. I have a cooling circuit arranged in series: (1) Heat exchanger (probability = 10^(-4)/requirement), (2) Pump (probability = 10^(-3)/requirement), (3) Heat exchanger (probability = 10^(-3)/requirement) and connection of pipes...
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    First criticality and initial heat-up of the reactor core

    please help me in understanding the following scenarios: 1. how could one approach first criticality in practice? 2. what would happen if we start-up with full power conditions from first criticality? 3. what would the shutdown requirement be in comparison to an equilibrium core? thank...
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    Final storage containing spent HTR fuel elements

    Astronuc "Are you assuming an infinite array of storage containers?" The problem does not state whether we have an infinite array of storage containers or certain number of containers. storage containers are in cylindrical shape.
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    Final storage containing spent HTR fuel elements

    can anyone help me with the following problem: I have been asked to estimate the rise in temperature in the salt in a final storage containing spent HTR-fuel elements in a time span of 100 years. Given the following data: Average heat flux 10 W/m; Heat capacity of salt 0.9 kJ/kg.K; density of...
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    Numerical Method Solutions ()

    I have been given the following problem as assignment: Find a numerical solution for the 1-D heat conduction (using the Explicit Method): \left\{\begin{array}U_{xx} = U_{t},\\ U(x,0) = \sin \pi x, \\ U(0,t) = U(1,t) = 0 Use h = 1, k = 0.005125 and M = 200. Can anyone help by giving...
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    Partial Differentiation Problem

    [Hyperreality] Okay, I haven't actually tried the problem, but you could try first to classify the pde (hyperbolic, elliptic, parabolic). In this case, the class of the pde depends on your choice of \rho . Have you tried it? [/Q] I don't know as to which class the PDE falls to. Let me state...
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    Partial Differentiation Problem

    Hi to all, I have been given the following problem as an assignment. \frac{\partial ^2 \phi}{\partial \rho^2} + \frac{1}{\rho}\frac{\partial \phi}{\partial \rho} + \frac{1}{\rho^2}\frac{\partial \phi}{\partial \chi^2} + \frac{\partial ^2 \phi}{\partial Z^2}+B^2\phi = 0 Here is my...
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    New Flux in a Sphere of moderator of Radius R

    Will it make any difference if someone used your first suggestion besides considering non-symmetrical problem? that's using.. \phi = A \frac{\sinh{-\frac{r}{L}}}{r} + B \frac{\cosh{\frac{r}{L}}}{r} + C Obviously using \phi = A \frac{\sinh{\frac{r}{L}}}{r} + B...
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    New Flux in a Sphere of moderator of Radius R

    Aha...you guys rock. \phi = A\frac{\sinh({-\frac{r}{L})}}{r} + \frac{S}{\Sigma_a} Solving for A using the extrapolated boundary condition, this is what I get. A = -\frac{S}{\Sigma_a} \frac{(R+d)}{ \sinh (-\frac{R+d}{L})} Substituting A \phi = \frac{S}{\Sigma_a}[1 -...
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    New Flux in a Sphere of moderator of Radius R

    I followed your suggestion but I'm getting a different E than yours. I believe you used the spherical coordinates E = \frac{L^2Sr}{D(2L^2 - r^2)} I will carry on to see if I could get the correct answer. Thanks to all...
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    New Flux in a Sphere of moderator of Radius R

    Thanks for all your replies...let met try Here is the Diffusion Equation (in spherical coordinates) for the problem \nabla^2\phi - \frac{1}{L^2}\phi = -\frac{S}{D} general solution \phi = A \frac{e^{-\frac{r}{L}}}{r} + B \frac{e^{\frac{r}{L}}}{r} + C A, B (homogeneous solution)...
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    New Flux in a Sphere of moderator of Radius R

    I have a problem where I must show that neutron flux in the sphere, for a sphere of moderator of radius R. This is one of the problems (5.14.a) in chapter 5 of "introduction to Nuclear Engineering" by J. R. Lamarsh. I would like to include the equation in this request but I'm unable to paste it...
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