A network thermodynamic analysis of the heat pipe

This work provides a unique view into the physics behind the heat pipe operation which was considered a thermal network of various components. Transient heat pipe behavior was described by first-order, linear, ordinary differential equations. The working fluid undergoes a thermodynamic cycle which was analyzed by T-s diagrams. The heat pipe dimensions must be "thermally compatible" with the heat pipe materials to establish the thermodynamic cycle. This was illustrated by a dimensionless number proposed here for the first time. Validated by comparisons with previous experimental and numerical studies, the present thermodynamic theory may lead to simplified heat pipe design schemes. (C) 1998 Elsevier Science Ltd. All rights reserved.