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Warm-up Time:

                                Watt-Hour / in²
Warm-up Time =    ^{__________________}   x  60        Minutes
                                   Watt / in²

                       (22.6 x 10^-3)
5/60 min. =   ^{________________}   x  60
                          Watt / in²

Solve the "time" equation for Watt / in²:

                     (22.6 x 10^-3)(60)
Watt / in² =    ^{__________________}    =  16.27
                          (5/60 min)

The effective emissivity between two parallel plates is given by:

                    1                                      1
e =   ^{__________________     =        ___________________}
        ( 1/e₁ + 1/e₂ - 1)            ( 1/.9 + 1/.93 - 1)

   = .84

Stefan-Boltzmann Law:

R = (.84)(36.58072 x 10 ^-12 )( ( T₁ )⁴ - ( T₂ )⁴ ) = 16.27

Where:  T₁ = Source Temperature
             T₂ = Average Water Temperature = (65+212)/2 = 138.5 °F (59 °C)
                   = 332.5 K

Solve the equation for the source temperature.



        = 858 K = 1084 °F (584 °C)

Results: The surface temperature of the source must be at least 1084 °F (584 °C) to evaporate 4 grams of water within 5 seconds.

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