here are several methods of investigating thermophys-ical properties of moulding sands but no one is universal.
Generally these methods belong to two categories.
Methods of testing under conditions of a steady heat flow
(a constant heat flux flowing through the selected mould-ing sand layer).
Methods of testing under conditions of an unsteady heat
flow through the selected moulding sand layer.
In the solution belonging to the first category, heating of the
moulding sand layer (sample) by the heating element is used
and then the directional heat flow is forced (unidirectional – for
flat samples, or axially symmetrical – for cylindrical samples
with the heat source situated in the axis). For the determination
of the thermal conductivity (2) one of the basic conduction
equations are used. This equation describes the dependence
between the thermal flux intensity (q), flowing through the
moulding sand layer of a thickness („l00) related to the surface
unit by the temperature gradient (at this thickness) – (T2 T1)
and by the thermal conductivity coefficient, equation (3