Mixing with diffusion

Description of mixing with diffusion and reaction in terms of the concept of material interfaces. Journal of Fluid Mechanics 114, 83-103. 

Mixing with Diffusion and Reaction. The interaction between diffusion, reactiontand mechanical mixing is illustrated for two prototype reaction schemes ... 

NOx emission requirements. This injeetion of steam reduees the temperature in the hot seetion, thus redueing the amount of NO produeed. When sprayed through the fuel nozzle, this steam ean impinge on the liner, thus ereating a temperature gradient, whieh ean lead to eraeks. Steam injeetion— whether it is required for NO eontrol or for extra power (5% steam by weight will produee 12% more work and inerease effieieney a few pereent)— must injeet steam into the eompressor diffuser to be safe and effeetive. This proeess will allow the steam to be fully mixed with the air before it enters the eombustor, redueing the ineidenee of liner failures due to steam injeetion. 

As can be seen from Fig. 5, both the Tg and T i states can mix with the S state but at different inter-radical distances X, At the point Jee cjj, X is small. The radical pair will not spend much time in this region either it will collapse to give a c-product or the two radicals will diffuse apart to the region where Jee and Tg-S mixing becomes possible. T i-S mixing is thus rather uncommon except where the radical separation is restricted by comjilexing or in a diradical (see Section IV). 

The presence of a liquid layer on the surface of the filter cake will cause solute to diffuse from the top layer of cake into the liquid. Also if disturbed the layer of liquid will mix with the surface layer of filter cake. This effect can be incorporated into the digital simulation by assuming a given initial depth of liquid as an additional segment of the bed which mixes at time t=0 with the top cake segment. The initial concentrations in the liquid layer and top cake segment are then found by an initial mass balance. 

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