Thermo-Fluid Analysis of Heat Pipe Using a Simple Yet Robust Numerical Approach

Abstract Numerical examination of thermal-hydraulic behavior in heat pipe aided thermal control system is challenging due to the multiregional and nonlinear nature of energy, mass transfer and flow dynamics. A comprehensive parametric thermo-fluid analysis of heat pipe is reported in this article using a simple yet robust numerical model considering fixed liquid–vapor interface. Navier–Stokes equations are solved in domain-specific formulations applied to each of regions: the porous liquid zone and the vapor core. Each domain is coupled to adjacent ones by ensuring continuity of mass, temperature and heat flux. The porous wick is simulated using the extended Darcy–Brinkman–Forchheimer formulation, accounting for both viscous and inertial effects in the saturated permeable structure. The internal saturation pressure is dynamically adjusted in response to varying heat input and different operating conditions. The simulation is first authenticated against published experimental and numerical results. Parametric analysis is then reported to examine the influence of key design and operational parameters, including heat input, sink temperature, pipe diameter, pipe length, wick thickness, and adiabatic section length. The results provide valuable insights for optimizing heat pipe geometry and performance, thus offering practical guidance for heat pipe driven thermal control system.