Temperature Model 1d Instructions

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Temperature diffusion through a linear rod. 1d temperature diffusion equation.

Animation showing temperature diffusion through rod.
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Animation showing temperature diffusion through rod.

Default setup:

  • Boundary conditions:
    1. 30 degrees Celcius on left boundary when t > 0
    2. 5 degrees Celcius in right boundary when t > 0
  • Initial Conditions:
    • 5 degrees Celcius for entire rod.

Software

Excel model file: Media:Temp-model-1d.xls

Equations

Governing equation for transient temperature diffusion

Image:Diffusion eqn T.png

Descretized equations:

  • Implicit equation
    <math> T^{t+1}_{i} = \frac{T^{t}_{i} + S \cdot T^{t+1}_{i+1} + S \cdot T^{t+1}_{i-1}}{1+2 \cdot S} </math>
    Image:Implicit_T.png
  • Explicit Equation
    <math> K \nabla^2 T = \frac{\partial T}{\partial t} </math>
    Image:Explicit_T.png
  • Where
    <math> S = \frac{K \Delta t}{\Delta x^2} </math>
    Image:T S function.png
    K = thermal conductivity (W/mK) [1]
    T = temperature (deg. Celcius or Kelvin)
    t = time (s)
    x = distance (m)
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