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Heat Transfer
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The heat transfer problems for thin plates are very analogous to the plane-parallel
problems and we will not discuss them especially.
Heat Sources
QuickField provides possibility to specify the heat sources located in the blocks, at
the edges or at the individual vertices of the model. The heat source specified at a
point of the xy-plane corresponds to a linear string-like heater which is perpendicular
to the plane of the model, and is described by the generated power per unit length. In
axisymmetric case the vertex heat source represents a heating circle around the axis
of symmetry or a point heater located on the axis. To incorporate both these cases a
total generated power value is associated with the vertex. For the heating circle the
total power is connected with its linear density by the relationship q = 2πr⋅ql.
Edge-bound heat source in the plane of model represents a surface heat source in
three-dimensional world. It is described by power per unit area and is specified by the
Neumann boundary condition for the edge. The volume power density associated
with a block corresponds to the volume heat source.
Boundary Conditions
The following boundary conditions can be specified at outward and inner boundaries
of the region.
Known temperature boundary condition (known also as boundary condition of the
first kind) specifies a known value of temperature T0 at the vertex or at the edge of
the model (for example on a liquid-cooled surface). T0 value at the edge can be
specified as a linear function of coordinates. The function parameters can vary from
one edge to another, but have to be adjusted to avoid discontinuities at edges' junction
points.
This boundary condition sometimes is called the boundary condition of the first kind.
Heat flux boundary condition (known also as boundary condition of the second
kind) is defined by the following equations:
Fn = -qs
 at outward boundaries,
Fn+ - Fn- = -qs
 at inner boundaries,
where Fn is a normal component of heat flux density, "+" and "−" superscripts denote
quantities to the left and to the right side of the boundary. For inner boundary qs,
denotes the generated power per unit area, for outward boundary it specifies the