Abstract
So far, only formal power series are known for this equation (except fundamental solution). In order to obtain closed expressions, especially, for the penetration parameter, we derive systematically an approximate solution (for Dirichlet boundary conditions). Although being very simple, it yields quite satisfactory results form≥1. This is demonstrated by numerical calculations.
Zusammenfassung
Bisher sind nur formale Potenzreihen-Lösungen für diese Gleichung bekannt. Um geschlossene Ausdrücke insbesondere für den Eindringparameter zu erhalten, leiten wir systematisch eine Näherungslösung ab (für Dirichletsche Randbedingungen). Trotz ihrer Einfachheit liefert sie ganz zufriedenstellende Ergebnisse fürm≥1, was durch numerische Rechnungen gezeigt wird.
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Enders, P. A simple, closed approximate solution for the diffusion equationc t=(c m cx) x . Warme - und Stoffubertragung 28, 139–140 (1993). https://doi.org/10.1007/BF01541110
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DOI: https://doi.org/10.1007/BF01541110