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"difficulty shifting", that is, there is an increase in viscosity; curve - strukture-
describes the viscous fluid pseudoplastic flow, which is typical for the "shear
softening" as a result of the destruction of the structure with increasing strain
rate; curve - nonlinear plastic body shows the non-linear plastic flow
characteristic for the majority of the plastic body after reaching the limit of shear
stress. Linear dependence - linear characteristic of the plastic body Bingham
body and conforms to the ideal plastic flow, after reaching the limit of shear
stress.
Thixotropic systems inherent isothermal recovery after the destruction of
the structure, as well as continuing its destruction (up to a certain limit) at
deformation.
Reopex system can be structured, that is to form the contacts between
particles resulting in weak turbulence or orientation by mechanical action with
small velocity gradients. A feature of many pseudoplastic and plastic - viscous
structured disperse systems such as coagulation is the presence of hysteresis
loops for loading and unloading. Rheogram area between the curve and the
ordinate axis is (at an appropriate scale) power density (per unit volume).
It consists of power Newtonian flow and power required at the same
velocity gradient to achieve this degree of destruction of the structure.
Power is proportional to the area between the two curves forming the
hysteresis loop, characterize the degree of approximation of the structure to
equilibrium.
In many processes, the product is subjected to intense mechanical stress
(pumps, mixers, etc.), that is, its structure reaches partially or substantially limit
the destruction. Therefore, when using the results of rheological studies for
practical purposes should be at least approximately, to choose the flow curve,
which corresponds to a given degree of destruction.
Accordingly, the calculation must use different processes characteristics
defined in the corresponding range of stresses and strains. a qualitative
assessment of the product and should be carried out on the most important
characteristics for a given process.
Mechanical processes - this process is purely mechanical interaction of
bodies. Processes that are determined not only by the laws of mechanics, and
hydrodynamics, called hydromechanical.
Mass transfer or diffusion processes associated with the transfer of material
in different states of aggregation from one phase to another. Heat exchange
processes associated with the transfer of heat from hotter bodies to less heated.
At the heart of a number of food production are chemical transformation of
substances, which cause changes in the properties and composition of these
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