The complementary equations used were the convective heat flow equations
assumed to be at various surfaces; the power heat flow equation
of the heating system, which represents the summation of the convective heat flow; and, finally, the equation that represents the relationshp between the power heat flow and two zones temperatures.
Unlike any previous instrument, the KD2 Pro uses the full exponential integral solution to the heat flow equation
for both single- and dual-needle sensors.
Pack melting and sublimation are calculated based on the heat flow equation
solution considering water phase changes.
These estimates utilize heat flow equations that are based on the same mathematical theory as moisture movement, and because of this, they also offer a way to further test the validity of Equations  and .
The validity of the inter-conversion method is further reinforced by an analysis of heating times as calculated by established heat flow equations applied to round and square cross-sectional dimensions.
When heating in saturated steam, it is possible to successfully estimate heating times of round and rectangular wood cross sections using a relatively straightforward solution to heat flow equations