Strona 2_redak - Instytut Agrofizyki im. Bohdana Dobrzańskiego ...

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PREFACE
In recent decades granular materials have gained great interest of both industrial
specialists and researchers. Growing competition on the global market, combined
with an increase in the scale of operations, enforced producers to use raw materials
and final products in granular form that is relatively easy for storage, handling and
processing. On the other hand, after fairly complete description of solid, liquid and
gaseous states of matter, scientists turned their attention to granular materials. With
their unique behaviour, some researchers postulate to consider this group of materials
as a separate state of matter. Research and technology developments made from the
sixties of the twentieth century resulted in a substantial progress in science and
technology in the field.
This work deals with some aspects of the mechanics of granular materials. It is
focused on the materials of biological origin used in agro and food technology. The
main features of agro and food materials that make them different from mineral
materials are strong influence of moisture content on mechanical behaviour and high
deformability of granules. These differences bring about certain peculiar behaviours
and necessity of adjustments of models of material, experimental techniques and
technological solutions.
While presenting this book, our purpose was to focus attention of the reader
on what we believe is important for understanding of the mechanical behaviour
of granular materials of biological origin. Selection of the presented material was
based on direct professional experience of the authors. The main theoretical
approaches – from the origins of soil mechanics to micropolar theory and DEM
modelling have been addressed. A review of commonly applied experimental
methods and material parameters has been presented. Finally, a catalogue of material
parameters drawn from laboratory testing of the authors was attached for reference as
well as for comparison with results of other laboratories. This “Mechanical Properties
of Granular Agro- Materials and Food Powders for Industrial Practice” is composed
of two volumes. Part I presents mainly issues relevant for storage and handling, while
Part II addresses questions of grinding and agglomeration.
We kindly acknowledge support given by the European Commission that
made this publication possible.
Authors