Chemical Engineering Science

Baffles in mixing tanks are necessary to achieve a high energy input. A similar energy input can be achieved by reverse mixing in an unbaffled vessel. This paper deals with performing stirring processes in a Reynolds number range between 550 and 38 900 by reversing the stirrer direction stepwise and periodically. An optimum time interval for switching the stirrer direction regarding the power inp…

Industrial catalyst particles are often non-spherical, but resolved calculations of diffusion and reaction are too expensive for repeated use in reactor-scale simulations. This paper derives a contour-averaged one-dimensional particle model by averaging the multidimensional diffusion equation over level sets of a scalar coordinate s ( x ). Particle geometry is retained through the differential vo…