The influence of turbulent fluctuations in temperature on NO formation rates is evaluated. It is shown that turbulent fluctuation may be neglected only whcnT#xAF;2/ T#xAF;2(E/RT#xAF;2) is much less than 1. When this condition is not satisfied the second and higher order moments in the temperature distribution will be important in determining NO formation. As a practical example, NO formation during the mixing of a hot air jet with a surrounding cold air jet is studied. A chopped Gaussian function is assumed to describe the temperature fluctuation distribution. Zel'dovich kinetics assuming steady-state N and equilibrium O atoms are used for NO formation. Comparison is made with rates calculated using mean temperatures. For the fully developed jet region the rates calculated with the chopped Gaussian were generally an order of magnitude higher than those obtained with mean temperatures. In the initial mixing region between the two jets the overall NO generation rates per unit length were similar, but the spatial distribution of rates was altered significantly. The importance of proper modeling of temperature fluctuations is clearly shown.
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