Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Dissipation due to heat conduction

  1. Nov 25, 2008 #1
    What is the dissipation due to heat conduction?

    [tex] D = -k \frac{\vec q\cdot\nabla T}{T} [/tex]

    where q is the heat flux, k is the
    coefficient of heat conduction and T is the absolut temperature.

    What is the physical meaning of this?
     
    Last edited by a moderator: Nov 25, 2008
  2. jcsd
  3. Nov 25, 2008 #2

    Mapes

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    This is a peculiar term. According to Fourier's law of conduction,

    [tex]\vec{q}\equiv -k\nabla T\mathrm{,}[/tex]

    so

    [tex]-k \frac{\vec q\cdot\nabla T}{T}=k^2\frac{\nabla ^2 T}{T}[/tex]

    with units of W2 m-4 K-1. In kinetic theory, this would correspond to [itex]Tk\dot{\sigma}[/itex], where [itex]\dot{\sigma}[/itex] is the volumetric rate of entropy creation. To my knowledge, this term isn't used for anything useful; are you certain about it?
     
    Last edited: Nov 26, 2008
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Dissipation due to heat conduction
  1. Heat conduction (Replies: 9)

  2. Heat Conduction (Replies: 14)

Loading...