Emissivity Definition and 57 Threads

  1. J

    Can High Emissivity IR Paint Solve Pyrometer Accuracy Issues on Steel Surfaces?

    I'm having problems measuring the temperature of a steel surface with varying emissivity with a pyrometer. So I thought one way to overcome the varying emissivity is to paint the surface with a paint that has a high uniform emissivity in the IR region. The paint should: Have high...
  2. C

    "Emissivity Problem - 8000K Plasma at 325nm

    Homework Statement I am given a plasma at 8000 Kelvin and assume its an ideal blackbody. I have slit of 0.01 cm^2, observing at wavelength 325 nm with a spectral bandwidth of 0.05 nm. The problem asks that the actually continuum under these conditions is 1 pW. What is the emissivity...
  3. G

    How Can You Calculate the Emissivity of Argon for Heat Transfer Analysis?

    Hi, Can anyone give me any information on where i could find information on the emissivity of a gas, particulally argon, or how i can calculate it? i am trying to create a graph of heat transfer against temperature and see which plays a larger role at particular temperatures when transfering...
  4. S

    Tungsten Filament Emissivity Assistance requested

    Hello, I have a Tungsten filament radiance source that has been calibrated in the UV region and would like to extrapolate the radiance to longer wavelengths. By calibrated, I mean, a NIST plot of spectral radiance v. wavelength at a certain set of operating conditions. I'm new to this...
    • seycyrus
    • Thread
    • Assistance Emissivity Filament Tungsten
    • Replies: 4
    • Forum: Other Physics Topics
  5. S

    Need help on this Light bulb Filament Temperature with emissivity and δ given

    Hi, I am stuck on this question, any help would be appreciated. Thanks! The tungsten filament of a certain 100 W light bulb radiates 2.85 W of light. (The other 97.15 is carried away by convection and conduction) The filament has surface area of 0.400 mm^2 and an emissivity of 0.952. Find...
  6. C

    Emissivity of a flat surface varies with zenith angle

    If the emissivity of a flat surface varies with zenith angle according to e=E*cos(theta) where E is the emissivity at zenith. Would this surface radiate isotropically? I think that because the emissivity varies then the emitted radiation varies accordingly so the energy measured from...
  7. C

    Emissivity e varies with zenith angle according to e = E*cos(theta)

    If the emissivity e varies with zenith angle according to e = E*cos(theta) where E is the emissivity normal to the surface. Would this surface be an isotropic source of radiation? Well, since e varies with angle then the flux density must vary accordingly so the surface would radiate...