Thane:
The solution of the differential equation of davefitz for a semi-infinite solid under transient conditions is as follows:
BC: T(0,t)=T(hot) (Constant surface temperature)
[T(x,t)-T(hot)]/[T(cold)-T(hot)]=erf[x/(2.SQRT(a.t))]
a=thermal diffusivity
erf=Gausian error function
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