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Doppler coefficient

  1. Oct 15, 2004 #1
    I know that the typical values of Doppler coefficient over core life are about -1 *10^-5 Deltak/k/°F at BOL and -1.5 * 10^-5 Deltak/k/°F at EOL.

    What are the value in SI units?

    Are they the same, but in Kelvin?

  2. jcsd
  3. Oct 18, 2004 #2


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    Since a Celsius degree [ not degree Celsius - but Celsius degree -
    the size of the interval ] is 9/5 a Fahrenheit degree - you can do the conversion.

    Celsius degree = 9/5 Fahrenheit degree.

    Divide by "Celsius degree":

    1 = 9/5 Fahrenheit degree / Celsius degree = 1.8 F deg / C deg

    Since this equals 1 - you can multiply any quantity by it without
    changing the value.

    If you take the BOL value of 1.0 * 10^-5 Delta k/k/F deg and multiply by
    the above, and divide out the units that cancel - you get

    1.8 * 10^-5 Delta k/ k / C deg = 1.8 * 10^-5 Delta k /k / Kelvin deg

    the latter part is because the size of the Kelvin degree equals the size
    of the Celsius degree.

    Dr. Gregory Greenman
    Physicist LLNL
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