Sommario
Si dimostra un risultato locale di esistenza e unicitá della soluzione di un problema con frontiera libera per il modello del nucleo in contrazione in reazioni gas-solido non catalitiche. Le condizioni sulla frontiera libera sono del tipo
con funztoni f e g generali soddisfacenti le ipotesi
Le condizioni di Wen e di Langmuir, che sono date rispettivamente daf(x)=-g(x)=x n(n>0) e daf(x) =-g(x)=a x n/(b+cx n) (a,b,c,n>0), rientrano entrambe nel presente schema.
Summary
We prove a local result in time for the existence and uniqueness of the solution of the free boundary problem in the shrinking core model for noncatalytic gas-solid reactions. We impose free boundary conditions of the type
with general functions g and f which satisfy the assumptions
The Wen and Langmuir conditions are given by,f(x)=-g(x)=x n(n>0) andf(x) =-g(x)=a x n/(b+cx n) (a,b,c,n>0), respectively, which both fulfill the above assumptions.
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This paper was finished while the first author was staying in the Istituto Matematico ≪Ulisse Dini≫ (Univ. di Firenze, Viale Morgagni 67A, (50134) Firenze, Italy), as a visiting professor of CNR-CNFM.
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Tarzia, D.A., Villa, L.T. On the free boundary problem in the wen-langmuir shrinking core model for noncatalytic gas-solid reactions. Meccanica 24, 86–92 (1989). https://doi.org/10.1007/BF01560134
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DOI: https://doi.org/10.1007/BF01560134