ABSTRACT
Application of the thermal boundary condition for a freeze pipe in finite element analysis of ground freezing often involves assuming a fixed temperature decay function for early stages of freezing followed by an assumption that the pipe surface is as cold, or nearly as cold as the chilled brine for the remainder of the freezing penod The combined heat transfer / fluid flow phenomenon at the inside wall of the freeze pipe is quite complex in theory, but it is readily dealt with using a heat flux boundary condition with modifier function option in the TEMP/W program Neglecting to properly account for the convective heat transfer phenomenon usually results in an optimistic estimate of freezing closure time as well as an over-estimate of how cold the ground directly adjacent to the freeze pipe becomes
