The Espresso Coffee Problem
We review the results of a long research project on the espresso coffee brewing process, carried out jointly by the industrial mathematics research group at the Department of Mathematics “U. Dini” of the University of Florence and the Italian company illycaffè s. p. a. (Trieste).
We describe the main experimental steps of the research and present the mathematical models developed in order to interpret the data correctly. The models are of increasing complexity, the first being confined to the mechanical phenomena (experiments performed with cold water), while the most comprehensive includes the influence of dissolution. Particular emphasis is put on the fact that the process deviates significantly from usual filtration in standard porous media, although the classical Darcy’s law is assumed as the fundamental flow mechanism.
KeywordsPorous Medium Fine Particle Free Boundary Injection Pressure Removal Process
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