The Influence of Device Geometry

A substantial increase in the mixing of the reaction mixture, caused by the effect of conical widening in the input section, resulted in the development of device geometry with hydrodynamic resistance in the form of consecutive narrowing and widening along the axis (diffuser-confusor transitions) [33]. 

Comparison of the turbulent diffusion coefficients in various zones of the tubular reactor (Table 2.2), has shown that a sufficiently uniform field is only achieved in the diffuser-confusor device. For real fast liquid-phase chemical processes, a reasonable solution is a diffuser-confusor type reactor with a diffuser opening angle yof 20 - 45°. 

In addition to the diffuser opening angle, y, the key parameters allowing the optimisation of turbulent mixing efficiency, in a diffuser-confusor reactor, are the diffuser to confusor diameter ratios dj/d and the length of the diffuser-confusor section L /dj. 

The maximnm average dissipation of specific kinetic energy of turbulisation e bas been selected as the optimisation criterion for the geometry of a tubular turbulent 

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