Evaluation of radial voidage profiles in packed beds of low aspect ratios

NÉSTOR JAVIER MARIANI; GERMÁN DÉLFOR MAZZA; OSVALDO MIGUEL MARTÍNEZ; GUILLERMO FERNANDO BARRETO

THE CANADIAN JOURNAL OF CHEMICAL ENGINEERING

Canadian Society for Chemical Engineering - Gilmore Printing Service Inc

Lugar: Otawa, Canadá; Año: 2000 vol. 78 p. 1133 - 1137

0008-4034

The relationship between the radial voidage profile e(r) and the radial distribution of particle centers f (r) is revised. A close expression is given for the section S(r, rC), the area of the segment of a cylindrical surface of radious r intersected by a particle centered at rC. From this expression e(r) can be evaluated straightforwardly from the knowledge of f(r). The range 1£ a £2 of aspect ratios (a =dT /dP ) is then analysed specifically. For this range, the distribution of spherical particles has been characterized theoretically (Govindarao et al. 1992) and a simple expression allows the evaluation of e(r). The use of this expression for actual catalyst particles, imperfect spheres showing a distribution of sizes, is finally analysed.