INVESTIGADORES
MAZZA German Delfor
congresos y reuniones científicas
Título:
Quantification of conductive heat transfer between immersed surfaces and the adjacent layer of particles in gas-fluidized beds
Autor/es:
N. J. MARIANI, G. D. MAZZA AND G. F. BARRETO
Lugar:
Universidad del País Vasco, Bilbao, España
Reunión:
Congreso; II EUROPEAN CONGRESS ON FLUIDIZATION; 1997
Institución organizadora:
Universidad del País Vasco, España
Resumen:
<!--
/* Font Definitions */
@font-face
{font-family:"Script MT Bold";
panose-1:3 4 6 2 4 6 7 8 9 4;
mso-font-charset:0;
mso-generic-font-family:script;
mso-font-pitch:variable;
mso-font-signature:3 0 0 0 1 0;}
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{mso-style-parent:"";
margin:0cm;
margin-bottom:.0001pt;
mso-pagination:widow-orphan;
font-size:12.0pt;
font-family:"Times New Roman";
mso-fareast-font-family:"Times New Roman";}
@page Section1
{size:595.3pt 841.9pt;
margin:70.85pt 3.0cm 70.85pt 3.0cm;
mso-header-margin:35.4pt;
mso-footer-margin:35.4pt;
mso-paper-source:0;}
div.Section1
{page:Section1;}
-->
The evaluation of the heat transfer coefficient
hwp between a heat exchanging
surface immersed in a fluidized bed and the adjacent layer of particles is
analysed in this work. Gas convective and radiant effects are not included
here.
The inclusion of hwp or an equivalent formulation, in mechanistic models
describing heat transfer has been necessary because the sudden voidage
variation close to the immersed wall restrains significantly the heat transfer
rate. However, there is not at present a widely accepted expression to evaluate
hwp.
A precise formulation of hwp accounting for transient conduction inside
spherical particles, the Smoluchowski effect, the concentration of particules
in the adjacent layer (Np) and an effective
separation gap (l0) is developed
here.